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1. Demonstrating multi-round subsystem quantum error correction using matching and maximum likelihood decoders

Author

Neereja Sundaresan, Theodore J. Yoder, Youngseok Kim, Muyuan Li, Edward H. Chen, Grace Harper, Ted Thorbeck, Andrew W. Cross, Antonio D. Córcoles, and Maika Takita

Subjects
Science
Abstract

Abstract Quantum error correction offers a promising path for performing high fidelity quantum computations. Although fully fault-tolerant executions of algorithms remain unrealized, recent improvements in control electronics and quantum hardware enable increasingly advanced demonstrations of the necessary operations for error correction. Here, we perform quantum error correction on superconducting qubits connected in a heavy-hexagon lattice. We encode a logical qubit with distance three and perform several rounds of fault-tolerant syndrome measurements that allow for the correction of any single fault in the circuitry. Using real-time feedback, we reset syndrome and flag qubits conditionally after each syndrome extraction cycle. We report decoder dependent logical error, with average logical error per syndrome measurement in Z(X)-basis of ~0.040 (~0.088) and ~0.037 (~0.087) for matching and maximum likelihood decoders, respectively, on leakage post-selected data.

Published
2023
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2. Implementing stakeholder engagement to explore alternative models of consent: An example from the PREP-IT trials

Author

Guillermo Pechero, Jr., MD, Branden Pfaff, Mayank Rao, David Pogorzelski, Paula McKay, Ella Spicer, Andrea Howe, Haley K. Demyanovich, Debra L. Sietsema, Michael F. McTague, Lolita Ramsey, Martha Holden, Joshua Rudnicki, Jeff Wells, Michelle Medeiros, Gerard P. Slobogean, Sheila Sprague, Jeffrey Wells, Mohit Bhandari, Robert V. O'Toole, Jean-Claude D'Alleyrand, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Theodore Manson, Jason Nascone, Ebrahim Paryavi, Raymond Pensy, Andrew Pollak, Marcus Sciadini, Yasmin Degani, Nathan N. O'Hara, Katherine Joseph, Megan Camara, Anthony D. Harris, Daniel C. Mullins, Lehana Thabane, Amber Wood, Gregory J. Della Rocca, Joan Hebden, Kyle J. Jeray, Lucas Marchand, Lyndsay M. O'Hara, Robert Zura, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, P.J. Devereaux, Gordon H. Guyatt, Diane Heels-Ansdell, Debra Marvel, Jana Palmer, Jeff Friedrich, Ms Frances Grissom, I. Leah Gitajn, Saam Morshed, Bradley A. Petrisor, Franca Mossuto, Manjari G. Joshi, Justin Fowler, Jessica Rivera, Max Talbot, Shannon Dodds, Alisha Garibaldi, Silvia Li, Uyen Nguyen, Alejandra Rojas, Taryn Scott, Gina Del Fabbro, Olivia Paige Szasz, Haley Demyanovich, Kelly Little, C. Daniel Mullins, Eric Kettering, Diamond Hale, Brad A. Petrisor, Herman Johal, Bill Ristevski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jordan Leonard, Francesc A. Marcano-Fernández, Jodi Gallant, Federico Persico, Marko Gjorgjievski, Annie George, Roman M. Natoli, Greg E. Gaski, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Joseph R. Baele, Brian H. Mullis, Lauren C. Hill, Andrea Hudgins, Patrick Osborn, Sarah Pierrie, Eric Martinez, Joseph Kimmel, John D. Adams, Michael L. Beckish, Christopher C. Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory K. Faucher, Richard W. Gurich, Jr., David E. Lazarus, S. John Millon, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, L. Edwin Rudisill, Jr., Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert M. Carlisle, II, Erin Adams Hofer, Brandon S. Huggins, Michael D. Hunter, William A. Marshall, Shea Bielby Ray, Cory D. Smith, Kyle M. Altman, Julia C. Bedard, Markus F. Loeffler, Erin R. Pichiotino, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, M. Christian Moody, Stephanie L. Tanner, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, Theodore Miclau, Utku Kandemir, Meir Marmor, Amir Matityahu, R. Trigg McClellan, Eric Meinberg, David Shearer, Paul Toogood, Anthony Ding, Erin Donohoe, Jothi Murali, Tigist Belaye, Eleni Berhaneselase, Alexandra Paul, Kartik Garg, Joshua L. Gary, Stephen J. Warner, John W. Munz, Andrew M. Choo, Timothy S. Achor, Milton L. “Chip” Routt, Guillermo Pechero, Adam Miller, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Kalia Sadasivan, Chris Koenig, Daniel Bailey, Daniel Wentworth, Chi Van, Justin Schwartz, Niloofar Dehghan, Clifford B. Jones, J. Tracy Watson, Michael McKee, Ammar Karim, Michael Talerico, Alyse Williams, Tayler Dykes, William T. Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip Mitchell, Karen Trochez, Andres Rodriguez, Vamshi Gajari, Elsa Rodriguez, Charles Pritchett, Christina Boulton, Jason Lowe, Jason Wild, John T. Ruth, Michel Taylor, Andrea Seach, Sabina Saeed, Hunter Culbert, Alejandro Cruz, Thomas Knapp, Colin Hurkett, Maya Lowney, Michael Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Francesc Marcano-Fernández, Montsant Jornet-Gibert, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Calavia, Guillem Graells-Alonso, Marta Martínez-Álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomó Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Ernesto Guerra-Farfan, Jordi Tomas-Hernandez, Jordi Teixidor-Serra, Vicente Molero-Garcia, Jordi Selga-Marsa, Juan Antonio Porcel-Vasquez, Jose Vicente Andres-Peiro, Joan Minguell-Monyart, Yaiza Garcia-Sanchez, Jorge Nuñez-Camarena, Eladia Tauste-Rubio, Marta Gonzalez-Amigo, Nicholas M. Romeo, Heather A. Vallier, Mary A. Breslin, Joanne Fraifogl, Eleanor S. Wilson, Leanne K. Wadenpfuhl, Paul G. Halliday, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Mauri Zomar, Chen “Brenda” Fan, Kyrsten Payne, Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Rachel Seymour, Christine Churchill, Claire Bartel, Robert Miles Mayberry, Maggie Brownrigg, Cara Girardi, Ada Mayfield, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, James S. Ahn, Farhanaz Panjshiri, Sharmistha Das, Antoinisha D. English, Sharon M. Haaser, Jaslynn A.N. Cuff, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, J. Brett Goodman, Martha B. Holden, Debra Bullard, Wendy Williams, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Lucas S. Marchand, Ashley Neese, Mark Russell, Zachary M. Olsen, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Clifford A. Reilly, Peter DePalo, Amy E. Hall, Marilyn Heng, Mitchel B. Harris, R. Malcolm Smith, David W. Lhowe, John G. Esposito, Mira Bansal, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Heather K. Champion, Leslie N. Johnson, Sheketha L. McGee, Eldrin L. Bhanat, Samir Mehta, Derek Donegan, Jaimo Ahn, Annamarie Horan, Mary Dooley, Ashley Kuczinski, Ashley Iwu, David Potter, Robert VanDemark, III, Troy Hollinsworth, Michael J. Weaver, Arvind G. von Keudell, Elizabeth M. Allen, Todd Jaeblon, Robert Beer, Mark J. Gage, Rachel M. Reilly, and Cindy Sparrow

Subjects
Cluster randomized crossover, Stakeholder engagement, Consent, Deferred consent, Trial design, Patient advisors, Medicine (General), R5-920
Abstract

Introduction: Cluster randomized crossover trials are often faced with a dilemma when selecting an optimal model of consent, as the traditional model of obtaining informed consent from participant's before initiating any trial related activities may not be suitable. We describe our experience of engaging patient advisors to identify an optimal model of consent for the PREP-IT trials. This paper also examines surrogate measures of success for the selected model of consent. Methods: The PREP-IT program consists of two multi-center cluster randomized crossover trials that engaged patient advisors to determine an optimal model of consent. Patient advisors and stakeholders met regularly and reached consensus on decisions related to the trial design including the model for consent. Patient advisors provided valuable insight on how key decisions on trial design and conduct would be received by participants and the impact these decisions will have. Results: Patient advisors, together with stakeholders, reviewed the pros and cons and the requirements for the traditional model of consent, deferred consent, and waiver of consent. Collectively, they agreed upon a deferred consent model, in which patients may be approached for consent after their fracture surgery and prior to data collection. The consent rate in PREP-IT is 80.7%, and 0.67% of participants have withdrawn consent for participation. Discussion: Involvement of patient advisors in the development of an optimal model of consent has been successful. Engagement of patient advisors is recommended for other large trials where the traditional model of consent may not be optimal.

Published
2021
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3. Managing work flow in high enrolling trials: The development and implementation of a sampling strategy in the PREPARE trial

Author

David Pogorzelski, Uyen Nguyen, Paula McKay, Lehana Thabane, Megan Camara, Lolita Ramsey, Rachel Seymour, J. Brett Goodman, Sheketha McGee, Joanne Fraifogl, Andrea Hudgins, Stephanie L. Tanner, Mohit Bhandari, Gerard P. Slobogean, Sheila Sprague, Jeffrey Wells, Jean-Claude D'Alleyrand, Anthony D. Harris, Daniel C. Mullins, Amber Wood, Gregory J. Della Rocca, Joan Hebden, Kyle J. Jeray, Lucas Marchand, Lyndsay M. O'Hara, Robert Zura, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, P.J. Devereaux, Gordon H. Guyatt, Diane Heels-Ansdell, Debra Marvel, Jana Palmer, Jeff Friedrich, Nathan N. O'Hara, Ms. Frances Grissom, I. Leah Gitajn, Saam Morshed, Robert V. O'Toole, Bradley A. Petrisor, Franca Mossuto, Manjari G. Joshi, Justin Fowler, Jessica Rivera, Max Talbot, Shannon Dodds, Alisha Garibaldi, Silvia Li, Alejandra Rojas, Taryn Scott, Gina Del Fabbro, Olivia Paige Szasz, Andrea Howe, Joshua Rudnicki, Haley Demyanovich, Kelly Little, C. Daniel Mullins, Michelle Medeiros, Eric Kettering, Diamond Hale, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Theodore Manson, Jason Nascone, Ebrahim Paryavi, Raymond Pensy, Andrew Pollak, Marcus Sciadini, Yasmin Degani, Haley K. Demyanovich, Katherine Joseph, Brad A. Petrisor, Herman Johal, Bill Ristevski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jordan Leonard, Francesc A. Marcano-Fernández, Jodi Gallant, Federico Persico, Marko Gjorgjievski, Annie George, Roman M. Natoli, Greg E. Gaski, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Joseph R. Baele, Brian H. Mullis, Lauren C. Hill, Patrick Osborn, Sarah Pierrie, Eric Martinez, Joseph Kimmel, John D. Adams, Michael L. Beckish, Christopher C. Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory K. Faucher, Richard W. Gurich, Jr., David E. Lazarus, S. John Millon, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, L. Edwin Rudisill, Jr., Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert M. Carlisle, II, Erin Adams Hofer, Brandon S. Huggins, Michael D. Hunter, William A. Marshall, Shea Bielby Ray, Cory D. Smith, Kyle M. Altman, Julia C. Bedard, Markus F. Loeffler, Erin R. Pichiotino, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, M. Christian Moody, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, Theodore Miclau, Utku Kandemir, Meir Marmor, Amir Matityahu, R. Trigg McClellan, Eric Meinberg, David Shearer, Paul Toogood, Anthony Ding, Erin Donohue, Tigist Belaye, Eleni Berhaneselase, Alexandra Paul, Kartik Garg, Joshua L. Gary, Stephen J. Warner, John W. Munz, Andrew M. Choo, Timothy S. Achor, Milton L. “Chip” Routt, Mayank Rao, Guillermo Pechero, Adam Miller, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Kalia Sadasivan, Chris Koenig, Daniel Bailey, Daniel Wentworth, Chi Van, Justin Schwartz, Niloofar Dehghan, Clifford B. Jones, J Tracy Watson, Michael McKee, Ammar Karim, Michael Talerico, Debra L. Sietsema, Alyse Williams, Tayler Dykes, William T. Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip Mitchell, Karen Trochez, Andres Rodriguez, Vamshi Gajari, Elsa Rodriguez, Charles Pritchett, Christina Boulton, Jason Lowe, Jason Wild, John T. Ruth, Michel Taylor, Andrea Seach, Sabina Saeed, Hunter Culbert, Alejandro Cruz, Thomas Knapp, Colin Hurkett, Maya Lowney, Michael Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Francesc Marcano-Fernández, Montsant Jornet-Gibert, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Calavia, Guillem Graells-Alonso, Marta Martínez-Álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomó Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Ernesto Guerra, Yaiza García, Nicholas M. Romeo, Heather A. Vallier, Mary A. Breslin, Eleanor S. Wilson, Leanne K. Wadenpfuhl, Paul G. Halliday, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Mauri Zomar, Ella Spicer, Chen “Brenda” Fan, Kyrsten Payne, Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Christine Churchill, Claire Bartel, Robert Miles Mayberry, Maggie Brownrigg, Cara Girardi, Ada Mayfield, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, James S. Ahn, Farhanaz Panjshiri, Sharmistha Das, Antoinisha D. English, Sharon M. Haaser, Jaslynn A.N. Cuff, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, Martha B. Holden, Debra Bullard, Wendy Williams, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Ashley Neese, Mark Russell, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Clifford A. Reilly, Peter DePalo, Amy E. Hall, Marilyn Heng, Mitchel B. Harris, R. Malcolm Smith, David W. Lhowe, John G. Esposito, Mira Bansal, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Heather K. Champion, Leslie N. Johnson, Sheketha L. McGee, Eldrin L. Bhanat, Samir Mehta, Derek Donegan, Jaimo Ahn, Annamarie Horan, Mary Dooley, Ashley Kuczinski, Ashley Iwu, David Potter, Robert VanDemark, III, Branden Pfaff, Troy Hollinsworth, Michael J. Weaver, Arvind G. von Keudell, Michael F. McTague, Elizabeth M. Allen, Todd Jaeblon, Robert Beer, Mark J. Gage, Rachel M. Reilly, and Cindy Sparrow

Subjects
Sampling, Pragmatic, Cluster crossover, Sampling framework, Work flow, Sampling strategy, Medicine (General), R5-920
Abstract

Introduction: Pragmatic trials in comparative effectiveness research assess the effects of different treatment, therapeutic, or healthcare options in clinical practice. They are characterized by broad eligibility criteria and large sample sizes, which can lead to an unmanageable number of participants, increasing the risk of bias and affecting the integrity of the trial. We describe the development of a sampling strategy tool and its use in the PREPARE trial to circumvent the challenge of unmanageable work flow. Methods: Given the broad eligibility criteria and high fracture volume at participating clinical sites in the PREPARE trial, a pragmatic sampling strategy was needed. Using data from PREPARE, descriptive statistics were used to describe the use of the sampling strategy across clinical sites. A Chi-square test was performed to explore whether use of the sampling strategy was associated with a reduction in the number of missed eligible patients. Results: 7 of 20 clinical sites (35%) elected to adopt a sampling strategy. There were 1539 patients excluded due to the use of the sampling strategy, which represents 30% of all excluded patients and 20% of all patients screened for participation. Use of the sampling strategy was associated with lower odds of missed eligible patients (297/4545 (6.5%) versus 341/3200 (10.7%) p

Published
2021
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4. Demonstration of quantum advantage in machine learning

Author

Diego Ristè, Marcus P. da Silva, Colm A. Ryan, Andrew W. Cross, Antonio D. Córcoles, John A. Smolin, Jay M. Gambetta, Jerry M. Chow, and Blake R. Johnson

Subjects
Physics, QC1-999, Electronic computers. Computer science, QA75.5-76.95
Abstract

Large advantage in small quantum computers Quantum computing promises to revolutionize all fields of science by solving problems that are too complex for conventional computers. However, the realization of a full-fledged, universal quantum computer is still far ahead, requiring millions of quantum bits and very low error rates. Despite this, D. Ristè and colleagues at Raytheon BBN Technologies, with collaborators at IBM, have demonstrated that a quantum advantage already appears with only a few quantum bits and a highly noisy system. The team solved a particular problem, known as learning parity with noise, using a five-qubit superconducting quantum processor. Counting the number of times that the processor runs, they demonstrate that the implemented quantum algorithm finds the solution much faster than by classical methods

Published
2017
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5. Experimental implementation of non-Clifford interleaved randomized benchmarking with a controlled-S gate

Author

Shelly Garion, Naoki Kanazawa, Haggai Landa, David C. McKay, Sarah Sheldon, Andrew W. Cross, and Christopher J. Wood

Subjects
Physics, QC1-999
Abstract

Hardware-efficient transpilation of quantum circuits to a quantum device native gate set is essential for the execution of quantum algorithms on noisy quantum computers. Typical quantum devices utilize a gate set with a single two-qubit Clifford entangling gate per pair of coupled qubits; however, in some applications access to a non-Clifford two-qubit gate can result in more optimal circuit decompositions and also allows more flexibility in optimizing over noise. We demonstrate calibration of a low-error non-Clifford controlled-π/2 phase (cs) gate on a cloud-based IBM Quantum system using the Qiskit Pulse framework. To measure the gate error of the calibrated cs gate we perform non-Clifford cnot-dihedral interleaved randomized benchmarking. We are able to obtain a gate error of 5.9(7)×10^{−3} at a gate length 263 ns, which is close to the coherence limit of the associated qubits, and lower error than the back-end standard calibrated cnot gate.

Published
2021
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6. Synthesis of CNOT-Dihedral circuits with optimal number of two qubit gates

Author

Shelly Garion and Andrew W. Cross

Subjects
Physics, QC1-999
Abstract

In this note we present explicit canonical forms for all the elements in the two-qubit CNOT-Dihedral group, with minimal numbers of controlled-$S$ ($CS$) and controlled-$X$ ($CX$) gates, using the generating set of quantum gates $[X, T, CX, CS]$. We provide an algorithm to successively construct the $n$-qubit CNOT-Dihedral group, asserting an optimal number of controlled-$X$ ($CX$) gates. These results are needed to estimate gate errors via non-Clifford randomized benchmarking and may have further applications to circuit optimization over fault-tolerant gate sets.

Published
2020
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7. Topological and Subsystem Codes on Low-Degree Graphs with Flag Qubits

Author

Christopher Chamberland, Guanyu Zhu, Theodore J. Yoder, Jared B. Hertzberg, and Andrew W. Cross

Subjects
Physics, QC1-999
Abstract

In this work we introduce two code families, which we call the heavy-hexagon code and the heavy-square code. Both code families are implemented by assigning physical data and ancilla qubits to both vertices and edges of low-degree graphs. Such a layout is particularly suitable for superconducting qubit architectures to minimize frequency collisions and cross talk. In some cases, frequency collisions can be reduced by several orders of magnitude. The heavy-hexagon code is a hybrid surface and Bacon-Shor code mapped onto a (heavy-) hexagonal lattice, whereas the heavy-square code is the surface code mapped onto a (heavy-) square lattice. In both cases, the lattice includes all the ancilla qubits required for fault-tolerant error correction. Naively, the limited qubit connectivity might be thought to limit the error-correcting capability of the code to less than its full distance. Therefore, essential to our construction is the use of flag qubits. We modify minimum-weight perfect-matching decoding to efficiently and scalably incorporate information from measurements of the flag qubits and correct up to the full code distance while respecting the limited connectivity. Simulations show that high threshold values for both codes can be obtained using our decoding protocol. Further, our decoding scheme can be adapted to other topological code families.

Published
2020
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8. Fault-tolerant magic state preparation with flag qubits

Author

Christopher Chamberland and Andrew W. Cross

Subjects
Physics, QC1-999
Abstract

Magic state distillation is one of the leading candidates for implementing universal fault-tolerant logical gates. However, the distillation circuits themselves are not fault-tolerant, so there is additional cost to first implement encoded Clifford gates with negligible error. In this paper we present a scheme to fault-tolerantly and directly prepare magic states using flag qubits. One of these schemes requires only three ancilla qubits, even with noisy Clifford gates. We compare the physical qubit and gate cost of our scheme to the magic state distillation protocol of Meier, Eastin, and Knill (MEK), which is efficient and uses a small stabilizer circuit. For low enough noise rates, we show that in some regimes the overhead can be improved by several orders of magnitude compared to the MEK scheme which uses Clifford operations encoded in the codes considered in this work.

Published
2019
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13. Quantum computing with Qiskit.

Author

Ali Javadi-Abhari, Matthew Treinish, Kevin Krsulich, Christopher J. Wood, Jake Lishman, Julien Gacon, Simon Martiel, Paul D. Nation, Lev S. Bishop, Andrew W. Cross, Blake R. Johnson, and Jay M. Gambetta

Published
2024
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22. The impact of heterotopic ossification prophylaxis after surgical fixation of acetabular fractures: national treatment patterns and related outcomes

Author

Adam Boissonneault, Nathan O Hara, David Pogorzelski, Lucas Marchand, Thomas Higgins, Leah Gitajn, Mark J. Gage, Roman M. Natoli, Ishani Sharma, Sarah Pierrie, Robert V O’Toole, Sheila Sprague, Gerard Slobogean, Gerard P. Slobogean, Jeffrey Wells, Mohit Bhandari, Anthony D. Harris, C. Daniel Mullins, Lehana Thabane, Amber Wood, Gregory J. Della Rocca, Joan Hebden, Kyle J. Jeray, Lucas S. Marchand, Lyndsay M. O'Hara, Robert Zura, Christopher Lee, Joseph Patterson, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, PJ Devereaux, Gordon H. Guyatt, Diane Heels-Ansdell, Debra Marvel, Jana Palmer Jeffrey Wells, Jeff Friedrich, Nathan N. O'Hara, Frances Grissom, I. Leah Gitajn, Saam Morshed, Robert V. O'Toole, Bradley A. Petrisor, Franca Mossuto, Manjari G. Joshi, Jean-Claude D'Alleyrand, Justin Fowler, Jessica Rivera, Max Talbot, Shannon Dodds, Silvia Li, Alejandra Rojas, Gina Del Fabbro, Olivia Paige Szasz, Paula McKay, Alexandra Minea, Andrea Howe, Haley Demyanovich, Michelle Medeiros, Genevieve Polk, Eric Kettering, Nirmen Mahal, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Jason Nascone, Raymond Pensy, Andrew Pollak, Marcus Sciadini, Yasmin Degani, Haley K. Demyanovich, Heather Phipps, Eric Hempen, Christine Holler, Brad A. Petrisor, Herman Johal, Bill Ristevski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jodi Gallant, Kaitlyn Pusztai, Sarah MacRae, Sara Renaud, John D. Adams, Michael L. Beckish, Christopher C. Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory K. Faucher, Richard W. Gurich, David E. Lazarus, S. John Millon, M. Christian Moody, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, L. Edwin Rudisill, Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert Carlisle, Erin A. Hofer, Brandon Huggins, Michael Hunter, William Marshall, Shea B. Ray, Cory Smith, Kyle M. Altman, Erin Pichiotino, Julia C. Quirion, Markus F. Loeffler, Erin R. Pichiotino, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, Matthew Anderson, Joshua Eskew, Benjamin Judkins, James M. Miller, Stephanie L. Tanner, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, Emily Bray, J. Wilson Sykes, Krystina Yoder, Kelsey Conner, Harper Abbott, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Brian H. Mullis, Yohan Jang, Luke A. Lopas, Lauren C. Hill, Courteney L. Fentz, Maricela M. Diaz, Krista Brown, Katelyn M. Garst, Emma W. Denari, Patrick Osborn, Maria Herrera, Theodore Miclau, Meir Marmor, Amir Matityahu, R. Trigg McClellan, David Shearer, Paul Toogood, Anthony Ding, Jothi Murali, Ashraf El Naga, Jennifer Tangtiphaiboontana, Tigist Belaye, Eleni Berhaneselase, Dmitry Pokhvashchev, William T Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip Mitchell, Karen Trochez, Elsa Rodriguez, Charles Pritchett, Natalie Hogan, A. Fidel Moreno, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Michael Talerico, Marybeth Horodyski, Marissa Pazik, Elizabeth Lossada-Soto, Joshua L. Gary, Stephen J Warner, John W. Munz, Andrew M. Choo, Timothy S. Achor, Milton L. 'Chip' Routt, Michael Kutzler, Sterling Boutte, Ryan J. Warth, Michael Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Christina Boulton, Jason Lowe, John T. Ruth, Brad Askam, Andrea Seach, Alejandro Cruz, Breanna Featherston, Robin Carlson, Iliana Romero, Isaac Zarif, Niloofar Dehghan, Michael McKee, Clifford B Jones, Debra L Sietsema, Alyse Williams, Tayler Dykes, Ernesto Guerra-Farfan, Jordi Tomas-Hernandez, Jordi Teixidor-Serra, Vicente Molero-Garcia, Jordi Selga-Marsa, Juan Antonio Porcel-Vazquez, Jose Vicente Andres-Peiro, Ignacio Esteban-Feliu, Nuria Vidal-Tarrason, Jordi Serracanta, Jorge Nuñez-Camarena, Maria del Mar Villar-Casares, Jaume Mestre-Torres, Pilar Lalueza-Broto, Felipe Moreira-Borim, Yaiza Garcia-Sanchez, Francesc Marcano-Fernández, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Calavia, Marta Martínez-Álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomó Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Vito Andriola, Matilde Molina-Corbacho, Yeray Maldonado-Sotoca, Alfons Gasset-Teixidor, Jorge Blasco-Moreu, Núria Fernández-Poch, Josep Rodoreda-Puigdemasa, Arnau Verdaguer-Figuerola, Heber Enrique Cueva-Sevieri, Santiago Garcia-Gimenez, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Ella Spicer, Kyrsten Payne, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, Greg E. Gaski, Jonathan Wills, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, J. Brett Goodman, Martha B. Holden, Wendy Williams, Taylor Hill, Ariel Brotherton, Nicholas M. Romeo, Heather A Vallier, Anna Vergon, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Zachary M. Olsen, Abby V. McGowan, Sophia Hill, Morgan K. Dauk, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Sheketha L. McGee, Eldrin L. Bhanat, Ugur Yener, Rajinder Khanna, Priyanka Nehete, Dr. David Potter, Dr. Robert VanDemark, Kyle Seabold, Nicholas Staudenmier, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Theresa A. Chockbengboun, Peter A. DePalo, Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Rachel Seymour, Christine Churchill, Ada Mayfield, Juliette Sweeney, Todd Jaeblon, Robert Beer, Brent Bauer, Sean Meredith, Sneh Talwar, Christopher M. Domes, Rachel M. Reilly, Ariana Paniagua, JaNell Dupree, Michael J. Weaver, Arvind G. von Keudell, Abigail E. Sagona, Samir Mehta, Derek Donegan, Annamarie Horan, Mary Dooley, Marilyn Heng, Mitchel B. Harris, David W. Lhowe, John G. Esposito, Ahmad Alnasser, Steven F. Shannon, Alesha N. Scott, Bobbi Clinch, Becky Weber, Michael J. Beltran, Michael T. Archdeacon, Henry Claude Sagi, John D. Wyrick, Theodore Toan Le, Richard T. Laughlin, Cameron G. Thomson, Kimberly Hasselfeld, Carol A. Lin, Mark S. Vrahas, Charles N. Moon, Milton T. Little, Geoffrey S. Marecek, Denice M. Dubuclet, John A. Scolaro, James R. Learned, Philip K. Lim, Susan Demas, Arya Amirhekmat, and Yan Marco Dela Cruz

Subjects
General Earth and Planetary Sciences, General Environmental Science
Published
2023
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31. Aqueous skin antisepsis before surgical fixation of open fractures (Aqueous-PREP): a multiple-period, cluster-randomised, crossover trial

Author

Gerard P. Slobogean, Sheila Sprague, Jeffrey L. Wells, Mohit Bhandari, Anthony D. Harris, C. Daniel Mullins, Lehana Thabane, Amber Wood, Gregory J. Della Rocca, Joan N. Hebden, Kyle J. Jeray, Lucas S. Marchand, Lyndsay M. O'Hara, Robert D. Zura, Christopher Lee, Joseph T. Patterson, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, PJ Devereaux, Gordon Guyatt, Diane Heels-Ansdell, Debra Marvel, Jana E. Palmer, Jeff Friedrich, Nathan N. O'Hara, Frances Grissom, I. Leah Gitajn, Saam Morshed, Robert V. O'Toole, Bradley Petrisor, Franca Mossuto, Manjari G. Joshi, Jean-Claude G. D'Alleyrand, Justin Fowler, Jessica C. Rivera, Max Talbot, David Pogorzelski, Shannon Dodds, Silvia Li, Gina Del Fabbro, Olivia Paige Szasz, Sofia Bzovsky, Paula McKay, Alexandra Minea, Kevin Murphy, Andrea L. Howe, Haley K. Demyanovich, Wayne Hoskins, Michelle Medeiros, Genevieve Polk, Eric Kettering, Nirmen Mahal, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Jason Nascone, Raymond Pensy, Andrew Pollak, Marcus Sciadini, Yasmin Degani, Heather Phipps, Eric Hempen, Herman Johal, Bill Ristevski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jodi L. Gallant, Kaitlyn Pusztai, Sarah MacRae, Sara Renaud, John D. Adams, Michael L. Beckish, Christopher C. Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory K. Faucher, Richard W. Gurich Jr, David E. Lazarus, S. John Millon, M. Christian Moody, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, L. Edwin Rudisill Jr, Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert Carlisle, Erin A. Hofer, Brandon Huggins, Michael Hunter, William Marshall, Shea B. Ray, Cory Smith, Kyle M. Altman, Erin R. Pichiotino, Julia C. Quirion, Markus F. Loeffler, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, Matthew Anderson, Joshua Eskew, Benjamin Judkins, James M. Miller, Stephanie L. Tanner, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, Emily Bray, J. Wilson Sykes, Krystina Yoder, Kelsey Conner, Harper Abbott, Roman M. Natoli, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Brian H. Mullis, Yohan Jang, Luke A. Lopas, Lauren C. Hill, Courteney L. Fentz, Maricela M. Diaz, Krista Brown, Katelyn M. Garst, Emma W. Denari, Patrick Osborn, Sarah N. Pierrie, Bradley Kessler, Maria Herrera, Theodore Miclau, Meir T. Marmor, Amir Matityahu, R. Trigg McClellan, David Shearer, Paul Toogood, Anthony Ding, Jothi Murali, Ashraf El Naga, Jennifer Tangtiphaiboontana, Tigist Belaye, Eleni Berhaneselase, Dmitry Pokhvashchev, William T. Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip P. Mitchell, Karen Trochez, Elsa Rodriguez, Charles Pritchett, Natalie Hogan, A. Fidel Moreno, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Michael Talerico, Marybeth Horodyski, Marissa Pazik, Elizabeth Lossada-Soto, Joshua L. Gary, Stephen J. Warner, John W. Munz, Andrew M. Choo, Timothy S. Achor, Milton L. 'Chip' Routt, Michael Kutzler, Sterling Boutte, Ryan J. Warth, Michael J. Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Christina Boulton, Jason Lowe, John T. Ruth, Brad Askam, Andrea Seach, Alejandro Cruz, Breanna Featherston, Robin Carlson, Iliana Romero, Isaac Zarif, Niloofar Dehghan, Michael McKee, Clifford B. Jones, Debra L. Sietsema, Alyse Williams, Tayler Dykes, Ernesto Guerra-Farfan, Jordi Tomas-Hernandez, Jordi Teixidor-Serra, Vicente Molero-Garcia, Jordi Selga-Marsa, Juan Antonio Porcel-Vazquez, Jose Vicente Andres-Peiro, Ignacio Esteban-Feliu, Nuria Vidal-Tarrason, Jordi Serracanta, Jorge Nuñez-Camarena, Maria del Mar Villar-Casares, Jaume Mestre-Torres, Pilar Lalueza-Broto, Felipe Moreira-Borim, Yaiza Garcia-Sanchez, Francesc Marcano-Fernández, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Calavia, Marta Martínez-Álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomó Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Vito Andriola, Matilde Molina-Corbacho, Yeray Maldonado-Sotoca, Alfons Gasset-Teixidor, Jorge Blasco-Moreu, Núria Fernández-Poch, Josep Rodoreda-Puigdemasa, Arnau Verdaguer-Figuerola, Heber Enrique Cueva-Sevieri, Santiago Garcia-Gimenez, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Ella Spicer, Kyrsten Payne, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, Greg E. Gaski, Jonathan Wills, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, J. Brett Goodman, Martha B. Holden, Wendy Williams, Taylor Hill, Ariel Brotherton, Nicholas M. Romeo, Heather A. Vallier, Anna Vergon, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Zachary M. Olsen, Abby V. McGowan, Sophia Hill, Morgan K. Dauk, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Sheketha L. McGee, Eldrin L. Bhanat, Ugur Yener, Rajinder Khanna, Priyanka Nehete, David Potter, Robert VanDemark III, Kyle Seabold, Nicholas Staudenmier, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Theresa A. Chockbengboun, Peter A. DePalo Sr., Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Rachel Seymour, Christine Churchill, Ada Mayfield, Juliette Sweeney, Todd Jaeblon, Robert Beer, Brent Bauer, Sean Meredith, Sneh Talwar, Christopher M. Domes, Mark J. Gage, Rachel M. Reilly, Ariana Paniagua, JaNell Dupree, Michael J. Weaver, Arvind G. von Keudell, Abigail E. Sagona, Samir Mehta, Derek Donegan, Annamarie Horan, Mary Dooley, Marilyn Heng, Mitchel B. Harris, David W. Lhowe, John G. Esposito, Ahmad Alnasser, Steven F. Shannon, Alesha N. Scott, Bobbi Clinch, Becky Weber, Michael J. Beltran, Michael T. Archdeacon, Henry Claude Sagi, John D. Wyrick, Theodore Toan Le, Richard T. Laughlin, Cameron G. Thomson, Kimberly Hasselfeld, Carol A. Lin, Mark S. Vrahas, Charles N. Moon, Milton T. Little, Geoffrey S. Marecek, Denice M. Dubuclet, John A. Scolaro, James R. Learned, Philip K. Lim, Susan Demas, Arya Amirhekmat, and Yan Marco Dela Cruz

Subjects
Adult, Male, Canada, Cross-Over Studies, Chlorhexidine, General Medicine, Antisepsis, Middle Aged, Fractures, Open, Anti-Infective Agents, Local, Humans, Surgical Wound Infection, Female, Povidone-Iodine
Abstract

Chlorhexidine skin antisepsis is frequently recommended for most surgical procedures; however, it is unclear if these recommendations should apply to surgery involving traumatic contaminated wounds where povidone-iodine has previously been preferred. We aimed to compare the effect of aqueous 10% povidone-iodine versus aqueous 4% chlorhexidine gluconate on the risk of surgical site infection in patients who required surgery for an open fracture.We conducted a multiple-period, cluster-randomised, crossover trial (Aqueous-PREP) at 14 hospitals in Canada, Spain, and the USA. Eligible patients were adults aged 18 years or older with an open extremity fracture treated with a surgical fixation implant. For inclusion, the open fracture required formal surgical debridement within 72 h of the injury. Participating sites were randomly assigned (1:1) to use either aqueous 10% povidone-iodine or aqueous 4% chlorhexidine gluconate immediately before surgical incision; sites then alternated between the study interventions every 2 months. Participants, health-care providers, and study personnel were aware of the treatment assignment due to the colour of the solutions. The outcome adjudicators and data analysts were masked to treatment allocation. The primary outcome was surgical site infection, guided by the 2017 US Centers for Disease Control and Prevention National Healthcare Safety Network reporting criteria, which included superficial incisional infection within 30 days or deep incisional or organ space infection within 90 days of surgery. The primary analyses followed the intention-to-treat principle and included all participants in the groups to which they were randomly assigned. This study is registered with ClinicalTrials.gov, NCT03385304.Between April 8, 2018, and June 8, 2021, 3619 patients were assessed for eligibility and 1683 were enrolled and randomly assigned to povidone-iodine (n=847) or chlorhexidine gluconate (n=836). The trial's adjudication committee determined that 45 participants were ineligible, leaving 1638 participants in the primary analysis, with 828 in the povidone-iodine group and 810 in the chlorhexidine gluconate group (mean age 44·9 years [SD 18·0]; 629 [38%] were female and 1009 [62%] were male). Among 1571 participants in whom the primary outcome was known, a surgical site infection occurred in 59 (7%) of 787 participants in the povidone-iodine group and 58 (7%) of 784 in the chlorhexidine gluconate group (odds ratio 1·11, 95% CI 0·74 to 1·65; p=0·61; risk difference 0·6%, 95% CI -1·4 to 3·4).For patients who require surgical fixation of an open fracture, either aqueous 10% povidone-iodine or aqueous 4% chlorhexidine gluconate can be selected for skin antisepsis on the basis of solution availability, patient contraindications, or product cost. These findings might also have implications for antisepsis of other traumatic wounds.US Department of Defense, Canadian Institutes of Health Research, McMaster University Surgical Associates, PSI Foundation.

Published
2022

35. Resource-Efficient Quantum Computing by Breaking Abstractions

Author

Margaret Martonosi, Casey Duckering, Prakash Murali, Ali Javadi Abhari, Natalie C. Brown, Christopher Chamberland, Kenneth R. Brown, Yongshan Ding, Frederic T. Chong, Andrew W. Cross, David Schuster, Pranav Gokhale, Jonathan M. Baker, and Yunong Shi

Subjects
Quantum Physics, Computer science, FOS: Physical sciences, Systems and Control (eess.SY), Parallel computing, Electrical Engineering and Systems Science - Systems and Control, 01 natural sciences, 010305 fluids & plasmas, Resource (project management), Qubit, 0103 physical sciences, FOS: Electrical engineering, electronic engineering, information engineering, Point (geometry), Abstraction, Electrical and Electronic Engineering, Quantum Physics (quant-ph), 010306 general physics, Quantum, Quantum computer
Abstract

Building a quantum computer that surpasses the computational power of its classical counterpart is a great engineering challenge. Quantum software optimizations can provide an accelerated pathway to the first generation of quantum computing applications that might save years of engineering effort. Current quantum software stacks follow a layered approach similar to the stack of classical computers, which was designed to manage the complexity. In this review, we point out that greater efficiency of quantum computing systems can be achieved by breaking the abstractions between these layers. We review several works along this line, including two hardware-aware compilation optimizations that break the quantum Instruction Set Architecture (ISA) abstraction and two error-correction/information-processing schemes that break the qubit abstraction. Last, we discuss several possible future directions., Invited paper by Proceedings of IEEE special issue

Published
2020
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40. Calibrated Decoders for Experimental Quantum Error Correction

Author

Edward H. Chen, Theodore J. Yoder, Youngseok Kim, Neereja Sundaresan, Srikanth Srinivasan, Muyuan Li, Antonio D. Córcoles, Andrew W. Cross, and Maika Takita

Subjects
Quantum Physics, J.2, FOS: Physical sciences, General Physics and Astronomy, Quantum Physics (quant-ph), 81P73 (Primary) 81P73 (Secondary)
Abstract

Arbitrarily long quantum computations require quantum memories that can be repeatedly measured without being corrupted. Here, we preserve the state of a quantum memory, notably with the additional use of flagged error events. All error events were extracted using fast, mid-circuit measurements and resets of the physical qubits. Among the error decoders we considered, we introduce a perfect matching decoder that was calibrated from measurements containing up to size-4 correlated events. To compare the decoders, we used a partial post-selection scheme shown to retain ten times more data than full post-selection. We observed logical errors per round of $2.2\pm0.1\times10^{-2}$ (decoded without post-selection) and $5.1\pm0.7\times10^{-4}$ (full post-selection), which was less than the physical measurement error of $7\times10^{-3}$ and therefore surpasses a pseudo-threshold for repeated logical measurements., 16 pages, 14 figures, 5 tables, for peer-review

Published
2021

41. Patient and stakeholder engagement learnings: PREP-IT as a case study

Author

Michelle Medeiros, T Rosie Love, Gerard P. Slobogean, Sheila Sprague, Eleanor M. Perfetto, Nathan N. O'Hara, C. Daniel Mullins, Jeffrey Wells, Mohit Bhandari, Jean-Claude D'alleyrand, Anthony Harris, Daniel C. Mullins, Lehana Thabane, Amber Wood, Gregory J. Della Rocca, Joan Hebden, Kyle J. Jeray, Lucas Marchand, Lyndsay M. O'Hara, Robert Zura, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, PJ Devereaux, Gordon H. Guyatt, Dianne Heels-Ansdell, Debra Marvel, Jana Palmer, Jeff Friedrich, Nathan O'Hara, Frances Grissom, Leah Gitajn, Saam Morshed, Robert O'Toole, Bradley A. Petrisor, Megan Camara, Franca Mossuto, Manjari G. Joshi, Justin Fowler, Jessica Rivera, Max Talbot, Shannon Dodds, Alisha Garibaldi, Silvia Li, Uyen Nguyen, David Pogorzelski, Alejandra Rojas, Taryn Scott, Gina Del Fabbro, Olivia Page Szasz, Paula McKay, Andrea Howe, Joshua Rudnicki, Haley Demyanovich, Kelly Little, Adam Boissonneault, Michellic Medeiros, Eric Kettering, Diamond Hale, Nirmen Mahal, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Theodore Manson, Jason Nascone, Ebrahim Paryavi, Raymond Pensy, Andrew Pollack, Marcus Sciadini, Yasmin Degani, Katherine Joseph, Lucas S. Marchand, Heather Phipps, Eric Hempen, Herman Johal, Bill Risteyski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jordan Leonard, Francesc A. Marcano-Fernández, Jodi Gallant, Federico Persico, Marko Gjorgjievski, Annie George, Sarah M. McGaugh, Kaitlyn Pusztai, Sarah Piekarski, Mavis Lyons, Julia Gennaccaro, Roman M. Natoli, Greg E. Gaski, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Joseph R. Baele, Brian H. Mullis, Yohan Jang, Luke A. Lopas, Lauren C. Hill, Andrea Hudgins, Courteney L. Fentz, Maricela M. Diaz, Katelyn M. Garst, Emma W. Denari, Patrick Osborn, Sarah Pierrie, Eric Martinez, Joseph Kimmel, Maria Herrera, John D. Adams, Michael Beckish, Christopher Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory Faucher, Richard W. Gurich Jr, David E. Lazarus, S. John Millon, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, Edwin L. Rudisill Jr, Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert M. Carlisle II, Erin Adams Hofer, Brandon S. Huggins, Michael D. Hunter, William A. Marshall, Shea Bielby Ray, Cory D. Smith, Kyle M. Altman, Julia C. Bedard, Markus F. Loeffler, Erin R. Pichiotino, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, M. Christian Moody, Matthew Anderson, Joshua Eskew, Benjamin Judkins, James M. Miller, Stephanie L. Tanner, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, John Wilson Sykes, Theodore Miclau, Utku Kandemir, Meir Marmor, Amir Matityahu, R. Trigg McClellan, Eric Meinberg, David Shearer, Paul Toogood, Anthony Ding, Erin Donohue, Jothi Murali, Ashraf El Naga, Jennifer Tangtiphaiboontana, Tigist Belaye, Eleni Berhaneselase, Alexandra Paul, Kartik Garg, Dmitry Pokhvashchev, Joshua L. Gary, Stephen J. Warner, John W. Munz, Andrew M. Choo, Timothy Achor, Milton L. \\'Chip\\' Routt, Mayank Rao, Guillermo Pechero, Adam Miller, Michael Kutzler, Sterling Boutte, Ryan J. Warth, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Kalia Sadasivan, Michael Talerico, Marybeth Horodyski, Chris Koenig, Daniel Bailey, Daniel Wentworth, Chi Van, Justin Schwartz, Marissa Pazik, Elizabeth Lossada-Soto, Niloofar Dehghan, Clifford B. Jones, J. Tracy Watson, Michael McKee, Ammar Karim, Debra L. Sietsema, Alyse William, Tayler Dykes, William T. Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip Mitchell, Karen Trochez, Andres Rodriguez, Vamshi Gajari, Elsa Rodriguez, Chris Pritchett, Natalie Hogan, Fidel A. Moreno, Christina Boulton, Jason Lowe, Jason Wild, John T. Ruth, Michel Taylor, Brad Askam, Andrea Seach, Sabina Saeed, Hunter Culbert, Alejandro Crus, Thomas Knapp, Colin Hurkett, Maya Lowney, Breanna Featherston, Robin Carlson, Iliana Romero, Isaac Zarif, Michael Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Francesc Marcano-Fernández, Montsant Jornet-Gibert, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Clavia, Guillem Graells-Alonso, Marta Martínez-álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomò Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Vito Andriola, Matilde Molina-Corbacho, Yeray Maldonado-Sotoca, Alfons Gasset-Teixidor, Jorge Blasco-Moreu, Núria Fernández-Poch, Josep Rodoreda-Puigdemasa, Arnau Verdaguer-Figuerola, Heber Enrique Cueva-Sevieri, Santiago Garcia-Gimenez, Ernesto Guerra-Farfán, Jordi Tomas-Hernandez, Jordi Teixidor-Serra, Vicente Molero-Garcia, Jordi Selga-Marsa, Juan Antonio Porcel-Vazquez, Jose Vicente Andres-Peiro, Joan Minguell-Monyart, Jorge Nuñez-Camarena, Maria del Mar Villar-Casares, Jaume Mestre-Torres, Pilar Lalueza-Broto, Felipe Moreira-Borim, Yaiza García, Nicholas M. Romeo, Heather A. Vallier, Mary A. Breslin, Joanne Fraifogl, Eleanor S. Wilson, Leanne K Wadenpfuhl, Paul G. Halliday, Isabella Heimke, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Mauri Zomar, Ella Spicer, Chen \\'Brenda\\' Fan, Kyrsten Payne, Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Rachel Seymour, Christine Churchill, Claire Bartel, Robert Miles Mayberry, Maggie Brownrigg, Cara Girardi, Ada Mayfield, Juliette Sweeney, Hannah Pollock, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, Jonathan Wills, Lolita Ramsey, James S. Ahn, Farhanaz Panjshiri, Sharmistha Das, Antoinisha D. English, Sharon M. Haaser, Jaslynn A.N. Cuff, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, J. Brett Goodman, Martha B. Holden, Debra Bullard, Wendy Williams, Taylor Hill, Ariel Brotherton, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Ashley Neese, Mark Russell, Zachary M. Olsen, Abby V. McGowan, Sophia Hill, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Clifford A Reily, Peter DePalo, Amy E. Hall, Rebecca E. Dabrowski, Theresa A. Chockbengboun, Marilyn Heng, Mitchel B. Harris, R. Malcolm Smith, David W. Lhowe, John Esposito, Mira Bansal, Michael McTague, Ahmad Alnasser, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Heather K. Champion, Leslie N. Johnson, Skeketha L. McGee, Eldrin L. Bhanat, Josny Thimothee, Jackie Serrano, Samir Mehta, Derek Donegan, Jaimo Ahn, Annamarie Horan, Mary Dooley, Ashley Kuczinski, Ashley Iwu, David Potter, Robert VanDemark II, Branden Pfaff, Troy Hollinsworth, Kristi Atkins, Michael J. Weaver, Arvind G. von Keudel, Michael F. McTague, Elizabeth M. Allen, Abigail E. Sagona, Todd Jaeblon, Robert Beer, Brent Bauer, Sean Meredith, Autumn Stone, Mark J. Gage, Rachel M. Reilly, Cindy Sparrow, Ariana Paniagua, Christopher M. Domes, Kristina P. Johnson, Steven F. Shannon, Alesha N. Scott, Bobbi Clinch, Carol A. Lin, Mark S. Vrahas, Charles N. Moon, Geoffrey S. Marecek, Denice Dubuclet, John A. Scolaro, James R. Learned, Philip K. Lim, Susan Demas, Michael J. Beltran, Michael T. Archdeacon, Henry Claude Sagi, John D. Wyrick, Theodore Toan Le, Richard T. Laughlin, and Cameron G. Thomson

Subjects
Patient Outcome Assessment, Medical education, business.industry, Stakeholder Participation, Health Policy, Patient-Centered Care, Stakeholder engagement, Medicine, Humans, Multi stakeholder, business, Patient centered
Published
2021

43. Critical faults of leakage errors on the surface code

Author

Andrew W. Cross, Natalie C. Brown, and Kenneth R. Brown

Subjects
Quantum Physics, Hardware_MEMORYSTRUCTURES, Computer science, Hardware_PERFORMANCEANDRELIABILITY, Topology, 01 natural sciences, 010305 fluids & plasmas, Hardware_GENERAL, Quantum error correction, Qubit, 0103 physical sciences, Hardware_INTEGRATEDCIRCUITS, Error correcting, Leakage (economics), 010306 general physics, Quantum, Subspace topology, Hardware_LOGICDESIGN, Electronic circuit, Quantum computer
Abstract

Leakage is a particularly damaging error that occurs when a qubit leaves the defined computational subspace. Leakage errors limit the effectiveness of quantum error correcting codes by spreading additional errors to other qubits and corrupting syndrome measurements. The effects of leakage errors on the surface code has been studied in various contexts. However, the effects of a leaked data qubit versus a leaked ancilla qubit can be quite different. Here, we study the effects of data leakage and ancilla leakage separately. We show that data leakage is much less damaging. We show that the surface code maintains its distance in the presence of leakage by either confining leakage to data qubits or eliminating aniclla qubit leakage at the critical fault location. We also introduce new techniques for handling leakage by using gates with one-sided leakage and by mixing two types of leakage reducing circuits: one to handle data leakage and one to handle ancilla leakage., Comment: comments welcome

Published
2020
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44. Managing work flow in high enrolling trials: The development and implementation of a sampling strategy in the PREPARE trial

Author

David Pogorzelski, Uyen Nguyen, Paula McKay, Lehana Thabane, Megan Camara, Lolita Ramsey, Rachel Seymour, J. Brett Goodman, Sheketha McGee, Joanne Fraifogl, Andrea Hudgins, Stephanie L. Tanner, Mohit Bhandari, Gerard P. Slobogean, Sheila Sprague, Jeffrey Wells, Jean-Claude D'Alleyrand, Anthony D. Harris, Daniel C. Mullins, Amber Wood, Gregory J. Della Rocca, Joan Hebden, Kyle J. Jeray, Lucas Marchand, Lyndsay M. O'Hara, Robert Zura, Michael J. Gardner, Jenna Blasman, Jonah Davies, Stephen Liang, Monica Taljaard, P.J. Devereaux, Gordon H. Guyatt, Diane Heels-Ansdell, Debra Marvel, Jana Palmer, Jeff Friedrich, Nathan N. O'Hara, Ms. Frances Grissom, I. Leah Gitajn, Saam Morshed, Robert V. O'Toole, Bradley A. Petrisor, Franca Mossuto, Manjari G. Joshi, Justin Fowler, Jessica Rivera, Max Talbot, Shannon Dodds, Alisha Garibaldi, Silvia Li, Alejandra Rojas, Taryn Scott, Gina Del Fabbro, Olivia Paige Szasz, Andrea Howe, Joshua Rudnicki, Haley Demyanovich, Kelly Little, C. Daniel Mullins, Michelle Medeiros, Eric Kettering, Diamond Hale, Andrew Eglseder, Aaron Johnson, Christopher Langhammer, Christopher Lebrun, Theodore Manson, Jason Nascone, Ebrahim Paryavi, Raymond Pensy, Andrew Pollak, Marcus Sciadini, Yasmin Degani, Haley K. Demyanovich, Katherine Joseph, Brad A. Petrisor, Herman Johal, Bill Ristevski, Dale Williams, Matthew Denkers, Krishan Rajaratnam, Jamal Al-Asiri, Jordan Leonard, Francesc A. Marcano-Fernández, Jodi Gallant, Federico Persico, Marko Gjorgjievski, Annie George, Roman M. Natoli, Greg E. Gaski, Todd O. McKinley, Walter W. Virkus, Anthony T. Sorkin, Jan P. Szatkowski, Joseph R. Baele, Brian H. Mullis, Lauren C. Hill, Patrick Osborn, Sarah Pierrie, Eric Martinez, Joseph Kimmel, John D. Adams, Michael L. Beckish, Christopher C. Bray, Timothy R. Brown, Andrew W. Cross, Timothy Dew, Gregory K. Faucher, Richard W. Gurich, David E. Lazarus, S. John Millon, M. Jason Palmer, Scott E. Porter, Thomas M. Schaller, Michael S. Sridhar, John L. Sanders, L. Edwin Rudisill, Michael J. Garitty, Andrew S. Poole, Michael L. Sims, Clark M. Walker, Robert M. Carlisle, Erin Adams Hofer, Brandon S. Huggins, Michael D. Hunter, William A. Marshall, Shea Bielby Ray, Cory D. Smith, Kyle M. Altman, Julia C. Bedard, Markus F. Loeffler, Erin R. Pichiotino, Austin A. Cole, Ethan J. Maltz, Wesley Parker, T. Bennett Ramsey, Alex Burnikel, Michael Colello, Russell Stewart, Jeremy Wise, M. Christian Moody, Rebecca G. Snider, Christine E. Townsend, Kayla H. Pham, Abigail Martin, Emily Robertson, Theodore Miclau, Utku Kandemir, Meir Marmor, Amir Matityahu, R. Trigg McClellan, Eric Meinberg, David Shearer, Paul Toogood, Anthony Ding, Erin Donohue, Tigist Belaye, Eleni Berhaneselase, Alexandra Paul, Kartik Garg, Joshua L. Gary, Stephen J. Warner, John W. Munz, Andrew M. Choo, Timothy S. Achor, Milton L. 'Chip' Routt, Mayank Rao, Guillermo Pechero, Adam Miller, Jennifer E. Hagen, Matthew Patrick, Richard Vlasak, Thomas Krupko, Kalia Sadasivan, Chris Koenig, Daniel Bailey, Daniel Wentworth, Chi Van, Justin Schwartz, Niloofar Dehghan, Clifford B. Jones, J Tracy Watson, Michael McKee, Ammar Karim, Michael Talerico, Debra L. Sietsema, Alyse Williams, Tayler Dykes, William T. Obremskey, Amir Alex Jahangir, Manish Sethi, Robert Boyce, Daniel J. Stinner, Phillip Mitchell, Karen Trochez, Andres Rodriguez, Vamshi Gajari, Elsa Rodriguez, Charles Pritchett, Christina Boulton, Jason Lowe, Jason Wild, John T. Ruth, Michel Taylor, Andrea Seach, Sabina Saeed, Hunter Culbert, Alejandro Cruz, Thomas Knapp, Colin Hurkett, Maya Lowney, Michael Prayson, Indresh Venkatarayappa, Brandon Horne, Jennifer Jerele, Linda Clark, Francesc Marcano-Fernández, Montsant Jornet-Gibert, Laia Martínez-Carreres, David Martí-Garín, Jorge Serrano-Sanz, Joel Sánchez-Fernández, Matsuyama Sanz-Molero, Alejandro Carballo, Xavier Pelfort, Francesc Acerboni-Flores, Anna Alavedra-Massana, Neus Anglada-Torres, Alexandre Berenguer, Jaume Cámara-Cabrera, Ariadna Caparros-García, Ferran Fillat-Gomà, Ruben Fuentes-López, Ramona Garcia-Rodriguez, Nuria Gimeno-Calavia, Guillem Graells-Alonso, Marta Martínez-Álvarez, Patricia Martínez-Grau, Raúl Pellejero-García, Ona Ràfols-Perramon, Juan Manuel Peñalver, Mònica Salomó Domènech, Albert Soler-Cano, Aldo Velasco-Barrera, Christian Yela-Verdú, Mercedes Bueno-Ruiz, Estrella Sánchez-Palomino, Ernesto Guerra, Yaiza García, Nicholas M. Romeo, Heather A. Vallier, Mary A. Breslin, Eleanor S. Wilson, Leanne K. Wadenpfuhl, Paul G. Halliday, Darius G. Viskontas, Kelly L. Apostle, Dory S. Boyer, Farhad O. Moola, Bertrand H. Perey, Trevor B. Stone, H. Michael Lemke, Mauri Zomar, Ella Spicer, Chen 'Brenda' Fan, Kyrsten Payne, Kevin Phelps, Michael Bosse, Madhav Karunakar, Laurence Kempton, Stephen Sims, Joseph Hsu, Christine Churchill, Claire Bartel, Robert Miles Mayberry, Maggie Brownrigg, Cara Girardi, Ada Mayfield, Robert A. Hymes, Cary C. Schwartzbach, Jeff E. Schulman, A. Stephen Malekzadeh, Michael A. Holzman, James S. Ahn, Farhanaz Panjshiri, Sharmistha Das, Antoinisha D. English, Sharon M. Haaser, Jaslynn A.N. Cuff, Holly Pilson, Eben A. Carroll, Jason J. Halvorson, Sharon Babcock, Martha B. Holden, Debra Bullard, Wendy Williams, Thomas F. Higgins, Justin M. Haller, David L. Rothberg, Ashley Neese, Mark Russell, Marcus Coe, Kevin Dwyer, Devin S. Mullin, Clifford A. Reilly, Peter DePalo, Amy E. Hall, Marilyn Heng, Mitchel B. Harris, R. Malcolm Smith, David W. Lhowe, John G. Esposito, Mira Bansal, Patrick F. Bergin, George V. Russell, Matthew L. Graves, John Morellato, Heather K. Champion, Leslie N. Johnson, Sheketha L. McGee, Eldrin L. Bhanat, Samir Mehta, Derek Donegan, Jaimo Ahn, Annamarie Horan, Mary Dooley, Ashley Kuczinski, Ashley Iwu, David Potter, Robert VanDemark, Branden Pfaff, Troy Hollinsworth, Michael J. Weaver, Arvind G. von Keudell, Michael F. McTague, Elizabeth M. Allen, Todd Jaeblon, Robert Beer, Mark J. Gage, Rachel M. Reilly, and Cindy Sparrow

Subjects
Pragmatic, medicine.medical_specialty, Comparative effectiveness research, Pharmacy, Sampling framework, Cluster crossover, Sampling strategy, Article, Odds, 03 medical and health sciences, 0302 clinical medicine, Health care, medicine, 030212 general & internal medicine, Sampling, Pharmacology, lcsh:R5-920, Descriptive statistics, business.industry, Sampling (statistics), General Medicine, Test (assessment), Work flow, Family medicine, business, lcsh:Medicine (General), 030217 neurology & neurosurgery
Abstract

Author(s): Pogorzelski, David; Nguyen, Uyen; McKay, Paula; Thabane, Lehana; Camara, Megan; Ramsey, Lolita; Seymour, Rachel; Goodman, J Brett; McGee, Sheketha; Fraifogl, Joanne; Hudgins, Andrea; Tanner, Stephanie L; Bhandari, Mohit; Slobogean, Gerard P; Sprague, Sheila; PREP-IT Investigators Executive Committee:; Steering Committee; Adjudication Committee; Data and Safety Monitoring Committee; Research Methodology Core; Patient Centred Outcomes Core; Orthopaedic Surgery Core; Operating Room Core; Infectious Disease Core; Military Core; McMaster University Methods Center; University of Maryland School of Medicine Administrative Center; University of Maryland School of Pharmacy, The PATIENTS Program; PREP-IT Clinical Sites: Lead Clinical Site (Aqueous-PREP and PREPARE); Aqueous-PREP and PREPARE; Aqueous-PREP; PREPARE; PREP-IT Investigators Executive Committee | Abstract: IntroductionPragmatic trials in comparative effectiveness research assess the effects of different treatment, therapeutic, or healthcare options in clinical practice. They are characterized by broad eligibility criteria and large sample sizes, which can lead to an unmanageable number of participants, increasing the risk of bias and affecting the integrity of the trial. We describe the development of a sampling strategy tool and its use in the PREPARE trial to circumvent the challenge of unmanageable work flow.MethodsGiven the broad eligibility criteria and high fracture volume at participating clinical sites in the PREPARE trial, a pragmatic sampling strategy was needed. Using data from PREPARE, descriptive statistics were used to describe the use of the sampling strategy across clinical sites. A Chi-square test was performed to explore whether use of the sampling strategy was associated with a reduction in the number of missed eligible patients.Results7 of 20 clinical sites (35%) elected to adopt a sampling strategy. There were 1539 patients excluded due to the use of the sampling strategy, which represents 30% of all excluded patients and 20% of all patients screened for participation. Use of the sampling strategy was associated with lower odds of missed eligible patients (297/4545 (6.5%) versus 341/3200 (10.7%) p l 0.001).ConclusionsImplementing a sampling strategy in the PREPARE trial has helped to limit the number of missed eligible patients. This sampling strategy represents a simple, easy to use tool for managing work flow at clinical sites and maintaining the integrity of a large trial.

Published
2020

45. Experimental implementation of non-Clifford interleaved randomized benchmarking with a controlled-S gate

Author

Andrew W. Cross, Sarah Sheldon, Shelly Garion, Naoki Kanazawa, H. Landa, David McKay, and Christopher J. Wood

Subjects
Quantum Physics, Computer science, business.industry, FOS: Physical sciences, Cloud computing, Benchmarking, Pulse (physics), Computer Science::Hardware Architecture, Open source, Computer Science::Emerging Technologies, Electronic engineering, Calibration, IBM, Hardware_ARITHMETICANDLOGICSTRUCTURES, business, Quantum Physics (quant-ph), Phase gate, Quantum computer, Hardware_LOGICDESIGN
Abstract

Hardware efficient transpilation of quantum circuits to a quantum devices native gateset is essential for the execution of quantum algorithms on noisy quantum computers. Typical quantum devices utilize a gateset with a single two-qubit Clifford entangling gate per pair of coupled qubits, however, in some applications access to a non-Clifford two-qubit gate can result in more optimal circuit decompositions and also allows more flexibility in optimizing over noise. We demonstrate calibration of a low error non-Clifford Controlled-$\frac{\pi}{2}$ phase (CS) gate on a cloud based IBM Quantum computing using the Qiskit Pulse framework. To measure the gate error of the calibrated CS gate we perform non-Clifford CNOT-Dihedral interleaved randomized benchmarking. We are able to obtain a gate error of $5.9(7) \times 10^{-3}$ at a gate length 263 ns, which is close to the coherence limit of the associated qubits, and lower error than the backends standard calibrated CNOT gate., Comment: 9 pages, 4 figures, references are updated, QPT curve in the Fig. 2 is updated based on new analysis procedure detailed in Appendix B. Conclusions unchanged

Published
2020
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46. Validating quantum computers using randomized model circuits

Author

Andrew W. Cross, P. D. Nation, Sarah Sheldon, Jay M. Gambetta, and Lev S. Bishop

Subjects
Physics, Quantum Physics, Measure (physics), Volume (computing), FOS: Physical sciences, Transmon, 01 natural sciences, 010305 fluids & plasmas, Computational science, 0103 physical sciences, Metric (mathematics), Rewriting, Quantum Physics (quant-ph), 010306 general physics, Quantum, Quantum computer, Electronic circuit
Abstract

We introduce a single-number metric, quantum volume, that can be measured using a concrete protocol on near-term quantum computers of modest size ($n\lesssim 50$), and measure it on several state-of-the-art transmon devices, finding values as high as 16. The quantum volume is linked to system error rates, and is empirically reduced by uncontrolled interactions within the system. It quantifies the largest random circuit of equal width and depth that the computer successfully implements. Quantum computing systems with high-fidelity operations, high connectivity, large calibrated gate sets, and circuit rewriting toolchains are expected to have higher quantum volumes. The quantum volume is a pragmatic way to measure and compare progress toward improved system-wide gate error rates for near-term quantum computation and error-correction experiments., Comment: 12 pages, 8 figures, closer to published version

Published
2019
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47. Topological and subsystem codes on low-degree graphs with flag qubits

Author

Andrew W. Cross, Jared Hertzberg, Theodore J. Yoder, Guanyu Zhu, and Christopher Chamberland

Subjects
Scheme (programming language), Computer science, QC1-999, General Physics and Astronomy, FOS: Physical sciences, Topology, 01 natural sciences, 010305 fluids & plasmas, Condensed Matter - Strongly Correlated Electrons, Computer Science::Emerging Technologies, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 010306 general physics, Quantum, computer.programming_language, Quantum Physics, Degree (graph theory), Strongly Correlated Electrons (cond-mat.str-el), Condensed Matter - Mesoscale and Nanoscale Physics, Physics, Qubit, Scalability, Error correcting, Quantum Physics (quant-ph), computer, Decoding methods, Flag (geometry)
Abstract

In this work we introduce two code families, which we call the heavy hexagon code and heavy square code. Both code families are implemented by assigning physical data and ancilla qubits to both vertices and edges of low degree graphs. Such a layout is particularly suitable for superconducting qubit architectures to minimize frequency collisions and crosstalk. In some cases, frequency collisions can be reduced by several orders of magnitude. The heavy hexagon code is a hybrid surface/Bacon-Shor code mapped onto a (heavy) hexagonal lattice whereas the heavy square code is the surface code mapped onto a (heavy) square lattice. In both cases, the lattice includes all the ancilla qubits required for fault-tolerant error-correction. Naively, the limited qubit connectivity might be thought to limit the error-correcting capability of the code to less than its full distance. Therefore, essential to our construction is the use of flag qubits. We modify minimum weight perfect matching decoding to efficiently and scalably incorporate information from measurements of the flag qubits and correct up to the full code distance while respecting the limited connectivity. Simulations show that high threshold values for both codes can be obtained using our decoding protocol. Further, our decoding scheme can be adapted to other topological code families., 20 pages, 21 figures, Comments welcome! V2 conforms to journal specifications

Published
2019

48. Fault-tolerant magic state preparation with flag qubits

Author

Andrew W. Cross and Christopher Chamberland

Subjects
Physics and Astronomy (miscellaneous), Computer science, FOS: Physical sciences, Hardware_PERFORMANCEANDRELIABILITY, Topology, 01 natural sciences, 010305 fluids & plasmas, law.invention, Computer Science::Hardware Architecture, Computer Science::Emerging Technologies, law, 0103 physical sciences, 010306 general physics, Distillation, Electronic circuit, Quantum Physics, Magic (illusion), Fault tolerance, Atomic and Molecular Physics, and Optics, lcsh:QC1-999, Logic gate, Qubit, Quantum Physics (quant-ph), AND gate, lcsh:Physics
Abstract

Magic state distillation is one of the leading candidates for implementing universal fault-tolerant logical gates. However, the distillation circuits themselves are not fault-tolerant, so there is additional cost to first implement encoded Clifford gates with negligible error. In this paper we present a scheme to fault-tolerantly and directly prepare magic states using flag qubits. One of these schemes uses a single extra ancilla, even with noisy Clifford gates. We compare the physical qubit and gate cost of this scheme to the magic state distillation protocol of Meier, Eastin, and Knill, which is efficient and uses a small stabilizer circuit. In some regimes, we show that the overhead can be improved by several orders of magnitude., 26 pages, 17 figures, 5 tables. Comments welcome! v2 (published version): quantumarticle documentclass and expanded discussions on the fault-tolerant schemes

Published
2019

49. Efficacy of a plasma-deposited, vancomycin/chitosan antibiotic coating for orthopaedic devices in a bacterially challenged rabbit model

Author

Jeremy Tzeng, Kyle J. Jeray, Liam O'Neill, Stephanie L. Tanner, Andrew W. Cross, Sarah M. Helms, Shayesteh Beladi Behbahani, Marian S. Kennedy, and John D. DesJardins

Subjects
010302 applied physics, Materials science, Alloy, technology, industry, and agriculture, Biofilm, Titanium alloy, 02 engineering and technology, Adhesion, engineering.material, equipment and supplies, 021001 nanoscience & nanotechnology, 01 natural sciences, Chitosan, chemistry.chemical_compound, chemistry, Coating, 0103 physical sciences, engineering, General Materials Science, Implant, 0210 nano-technology, Nitriding, Nuclear chemistry
Abstract

This study investigated the efficacy of co-deposited vancomycin/chitosan coatings prepared using a plasma process on metallic implants in a bacterially challenged rabbit model. A BioDepTM plasma coating process was used to deposit thin layers of chitosan with vancomycin onto titanium alloy surfaces. Coated implants were examined using standard microscopy, profilometry and elution studies. Nitrided titanium alloy Ti-6Al-4V (Ti alloy) dynamic compression plates (DCP) (n=45) were implanted onto rabbit femurs and then challenged with a bacterial inoculum prior to closure. Three treatment groups were compared: an unmodified Ti alloy DCP that was considered the control, a DCP with the antibacterial coating of chitosan with vancomycin, and a DCP first blasted with alumina grit followed by a coating of chitosan with vancomycin. Bone, surrounding soft tissue, and implants were harvested after 28 days for bacterial quantification. The thin coating of chitosan and vancomycin was clearly detected on the implant surfaces after the plasma coating process. This coating eluted antimicrobial agents and prevented bacterial adhesion, regardless of surface roughness, and prevented biofilm formation compared to the control Ti alloy DCP. The blasting of the Ti alloy implant surface with alumina grit resulted in both roughening and partial implantation of the alumina particles, but did not alter the short-term antimicrobial effects of the chitosan/vancomycin coating. This study suggests that the plasma process is capable of depositing an antimicrobial agent directly onto the surface of metallic implants and that this vancomycin/chitosan coating may prove to be a useful pathway to prevent short-term biofilm formation.

Published
2021
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50. 99DOTS

Author

Andrew W. Cross, Reena Kuttan, Brandon Liu, Raghuram Rao, Amy Z Chen, William Thies, Rashmi Rodrigues, George D'Souza, Amar Shah, Deepti Chittamuru, Vinod Choudhary, Abhishek Kumar, Bhavin Vadera, Vineet Nair, Daksha Shah, Vineet K. Chadha, Sameer Kumta, Puneet Dewan, Bruce Thomas, Priyanka Ivatury, Nakull Gupta, Kiran Rade, and Kshama Lakshman

Subjects
Tuberculosis in India, Iterative design, Computer science, 030231 tropical medicine, Cost approach, Medication adherence, 03 medical and health sciences, 0302 clinical medicine, Risk analysis (engineering), Software deployment, Phone, Scale (social sciences), Global health, 030212 general & internal medicine
Abstract

Ensuring that patients adhere to prescribed medication remains an important challenge in global health. While technology has been utilized to monitor and improve adherence, solutions to date have been too costly for large-scale deployment in developing regions. This paper describes 99DOTS, a low-cost approach for tracking adherence using a combination of paper packaging and low-end mobile phones. Every day, patients reveal an unpredictable phone number behind the pills and send a free call to that number to indicate that drugs were dispensed and taken. Within five years of its inception, 99DOTS has become a standard of care for tuberculosis in India and has enrolled over 200,000 patients. We provide a holistic account of the project's evolution, including its iterative design, scaled implementation, and lessons learned along the way. We hope this account will serve as a useful case study for anyone seeking to establish and scale new low-cost technologies for a global audience.

Published
2019
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