1. Time-crystalline eigenstate order on a quantum processor
- Author
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Julian Kelly, Alexander Bilmes, Vedika Khemani, Seon Kim, Alexei Kitaev, Murphy Yuezhen Niu, J. Hilton, Orion Martin, Craig Gidney, Bob B. Buckley, Thomas E. O'Brien, Jarrod R. McClean, Alexander N. Korotkov, Pavel Laptev, Tanuj Khattar, Sabrina Hong, Daniel Eppens, Alan Ho, Aditya Locharla, Ofer Naaman, Ping Yeh, Juan Atalaya, Sean D. Harrington, Frank Arute, Roberto Collins, Joao Marcos Vensi Basso, Doug Strain, Matthew P. Harrigan, Zhang Jiang, Joonho Lee, Ami Greene, Alan R. Derk, Roderich Moessner, Bálint Pató, William J. Huggins, Trevor McCourt, Ashley Huff, Joseph C. Bardin, Andre Petukhov, Fedor Kostritsa, Michael Newman, Cody Jones, Sean Demura, Shivaji Lal Sondhi, B. Burkett, Sergio Boixo, Jonathan H. Gross, David A. Buell, Kevin J. Satzinger, Michael Broughton, Daniel Sank, Masoud Mohseni, Lev Ioffe, Yuan Su, Shirin Montazeri, Xiao Mi, Eric Ostby, Marissa Giustina, David Landhuis, Z. Jamie Yao, Kenny Lee, Kunal Arya, Pedram Roushan, Hartmut Neven, Sergei V. Isakov, Andrew Dunsworth, Zijun Chen, Matteo Ippoliti, Matthew Neeley, Nicholas C. Rubin, Austin G. Fowler, Anthony Megrant, Marco Szalay, Trent Huang, Evan Jeffrey, Leon Brill, Justin Iveland, Paul V. Klimov, Matthew D. Trevithick, William Courtney, Nicholas Bushnell, Theodore White, Alexandre Bourassa, E. Lucero, Edward Farhi, Vladimir Shvarts, Dripto M. Debroy, Benjamin Villalonga, Wojciech Mruczkiewicz, Chris Quintana, Juhwan Yoo, Benjamin Chiaro, Dvir Kafri, Brooks Foxen, Vadim Smelyanskiy, Ryan Babbush, Kostyantyn Kechedzhi, Charles Neill, Yu Chen, Andreas Bengtsson, Matt McEwen, A. Opremcak, Kevin C. Miao, Adam Zalcman, and Catherine Erickson
- Subjects
Thermal equilibrium ,Physics ,Phase transition ,Multidisciplinary ,Quantum decoherence ,Quantum information ,Quantum simulator ,Article ,Phase Transition ,Cold Temperature ,Phase transitions and critical phenomena ,Qubit ,Thermodynamics ,Statistical physics ,Quantum simulation ,Quantum ,Quantum computer - Abstract
Quantum many-body systems display rich phase structure in their low-temperature equilibrium states1. However, much of nature is not in thermal equilibrium. Remarkably, it was recently predicted that out-of-equilibrium systems can exhibit novel dynamical phases2–8 that may otherwise be forbidden by equilibrium thermodynamics, a paradigmatic example being the discrete time crystal (DTC)7,9–15. Concretely, dynamical phases can be defined in periodically driven many-body-localized (MBL) systems via the concept of eigenstate order7,16,17. In eigenstate-ordered MBL phases, the entire many-body spectrum exhibits quantum correlations and long-range order, with characteristic signatures in late-time dynamics from all initial states. It is, however, challenging to experimentally distinguish such stable phases from transient phenomena, or from regimes in which the dynamics of a few select states can mask typical behaviour. Here we implement tunable controlled-phase (CPHASE) gates on an array of superconducting qubits to experimentally observe an MBL-DTC and demonstrate its characteristic spatiotemporal response for generic initial states7,9,10. Our work employs a time-reversal protocol to quantify the impact of external decoherence, and leverages quantum typicality to circumvent the exponential cost of densely sampling the eigenspectrum. Furthermore, we locate the phase transition out of the DTC with an experimental finite-size analysis. These results establish a scalable approach to studying non-equilibrium phases of matter on quantum processors., A study establishes a scalable approach to engineer and characterize a many-body-localized discrete time crystal phase on a superconducting quantum processor.
- Published
- 2021