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2. Co-GISAXS as a New Technique to Investigate Surface Growth Dynamics

Author

Rainville, Meliha G., Hoskin, Christa, Ulbrandt, Jeffrey G., Narayanan, Suresh, Sandy, Alec R., Zhou, Hua, Headrick, Randall L., and Ludwig Jr, Karl F.

Subjects
Condensed Matter - Materials Science
Abstract

Detailed quantitative measurement of surface dynamics during thin film growth is a major experimental challenge. Here X-ray Photon Correlation Spectroscopy with coherent hard X-rays is used in a Grazing-Incidence Small-Angle X-ray Scattering (i.e. Co-GISAXS) geometry as a new tool to investigate nanoscale surface dynamics during sputter deposition of a-Si and a-WSi$_2$ thin films. For both films, kinetic roughening during surface growth reaches a dynamic steady state at late times in which the intensity autocorrelation function $g_2$(q,t) becomes stationary. The $g_2$(q,t) functions exhibit compressed exponential behavior at all wavenumbers studied. The overall dynamics are complex, but the most surface sensitive sections of the structure factor and correlation time exhibit power law behaviors consistent with dynamical scaling., Comment: 32 pages, 12 figures

Published
2015
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3. Using coherent X-rays to directly measure the propagation velocity of defects during thin film deposition

Author

Ulbrandt, Jeffrey G., Rainville, Meliha G., Hoskin, Christa, Narayanan, Suresh, Sandy, Alec R., Zhou, Hua, Ludwig Jr., Karl F., and Headrick, Randall L.

Subjects
Condensed Matter - Materials Science
Abstract

The properties of artificially grown thin films are often strongly affected by the dynamic relationship between surface growth processes and subsurface structure. Coherent mixing of X-ray signals promises to provide an approach to better understand such processes. Here, we demonstrate the continuously variable mixing of surface and bulk scattering signals during real-time studies of sputter deposition of a-Si and a-WiS2 films by controlling the X-ray penetration and escape depths in coherent grazing incidence small angle X-ray scattering (Co-GISAXS). Under conditions where the X-ray signal comes from both the growth surface and the thin film bulk, oscillations in temporal correlations arise from coherent interference between scattering from stationary bulk features and from the advancing surface. We also observe evidence that elongated bulk features propagate upward at the same velocity as the surface. Additionally, a highly surface sensitive mode is demonstrated that can access the surface dynamics independently of the subsurface structure., Comment: Revised version. 5 figures, 27 pages

Published
2015

4. Advanced Computational Technologies for Experiment Control, Data Acquisition, and Data Analysis at the Advanced Photon Source

Author

Hammonds, John, primary, Henke, Steven, additional, Jemian, Pete R., additional, Kandel, Saugat, additional, Parraga, Hannah, additional, Rebuffi, Luca, additional, Shi, Xianbo, additional, Veseli, Siniša, additional, Wolfman, Mark, additional, Wyman, Max, additional, Zhou, Tao, additional, Chard, Ryan, additional, Cote, Benoit, additional, Allcock, William, additional, Assoufid, Lahsen, additional, Cherukara, Mathew J., additional, Kelly, Shelly, additional, Sandy, Alec, additional, Sullivan, Joseph, additional, and Schwarz, Nicholas, additional

Published
2024
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8. Intermittent Defect Fluctuations in Oxide Heterostructures

Author

Zhang, Qingteng, primary, Wan, Gang, additional, Starchenko, Vitalii, additional, Hu, Guoxiang, additional, Dufresne, Eric M., additional, Zhou, Hua, additional, Jeen, Hyoungjeen, additional, Almazan, Irene Calvo, additional, Dong, Yongqi, additional, Liu, Huajun, additional, Sandy, Alec R., additional, Sterbinsky, George E., additional, Lee, Ho Nyung, additional, Ganesh, P., additional, and Fong, Dillon D., additional

Published
2023
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10. 5G Enabled Energy Innovation: Advanced Wireless Networks for Science, Workshop Report

Author

Beckman, Pete, primary, Catlett, Charlie, additional, Ahmed, Moinuddin, additional, Alawad, Mohammed, additional, Bai, Linquan, additional, Balaprakash, Prasanna, additional, Barker, Kevin, additional, Beckman, Pete, additional, Berry, Randall, additional, Bhuyan, Arup, additional, Brebner, Gordon, additional, Burkes, Klaehn, additional, Butko, Anastasiia, additional, Cappello, Franck, additional, Chard, Ryan, additional, Collis, Scott, additional, Cree, Johnathan, additional, Dasgupta, Dipankar, additional, Evdokimov, Anatoly, additional, Fields, Jason M, additional, Fuhr, Peter, additional, Harper, Colby, additional, Jin, Yier, additional, Kettimuthu, Rajkumar, additional, Kiran, Mariam, additional, Kozma, Robert, additional, Kumar, Praveen Ashok, additional, Kumar, Yatish, additional, Luo, Linqing, additional, Mashayekhy, Lena, additional, Monga, Inder, additional, Nickless, Bill, additional, Pappas, Thrasyvoulos, additional, Peterson, Elena, additional, Pfeffer, Trever, additional, Rakheja, Shaloo, additional, Tribaldos, Veroica Rodriguez, additional, Rooke, Sterling, additional, Roy, Sumit, additional, Saadawi, Tarek, additional, Sandy, Alec, additional, Sankaran, Rajesh, additional, Schwarz, Nicholas, additional, Somnath, Suhas, additional, Stan, Marius, additional, Stuart, Cory, additional, Sullivan, Ryan, additional, Sumant, Anirudha, additional, Tchilinguirian, Greg, additional, Tran, Nhan, additional, Veeramany, Arun, additional, Wang, Angela, additional, Wang, Bin, additional, Wiedlea, Andrew, additional, Wielandt, Stijn, additional, Windus, Theresa, additional, Wu, Yuxin, additional, Yang, Xi, additional, Yao, Zhi, additional, Yu, Rose, additional, Zeng, Yuping, additional, and Zhang, Yuepeng, additional

Published
2020
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11. Advanced Computational Technologies for Experiment Control, Data Acquisition, and Data Analysis at the Advanced Photon Source.

Author

Hammonds, John, Henke, Steven, Jemian, Pete R., Kandel, Saugat, Parraga, Hannah, Rebuffi, Luca, Shi, Xianbo, Veseli, Siniša, Wolfman, Mark, Wyman, Max, Zhou, Tao, Chard, Ryan, Cote, Benoit, Allcock, William, Assoufid, Lahsen, Cherukara, Mathew J., Kelly, Shelly, Sandy, Alec, Sullivan, Joseph, and Schwarz, Nicholas

Subjects
SCIENTIFIC knowledge, SUPERCOMPUTERS, ACQUISITION of data, REAL-time computing, DATA analysis, ONLINE data processing
Abstract

The article discusses the ongoing upgrade of the Advanced Photon Source (APS) and the implementation of advanced computational technologies for experiment control, data acquisition, and data analysis. The upgrade aims to make the APS the brightest hard X-ray synchrotron light source in the world. The article highlights the use of automated optics alignment and artificial intelligence/machine learning approaches for improved precision and efficiency in experiments. It also describes the development of a new control system for a spectroscopy beamline using Bluesky and Ophyd, which has already enabled user experiments during commissioning. The article emphasizes the importance of these advancements in handling the increasing volume of data generated at the APS and improving research opportunities. The APS is partnering with the Argonne Leadership Computing Facility (ALCF) to provide streamlined computing capabilities for researchers, including dedicated computing allocations and standardized processing workflows. The APS has also implemented a Fast Autonomous Scanning Toolkit (FAST) that uses neural networks and efficient hardware controls for scanning microscopy experiments. These advancements will enhance the capabilities of the APS and facilitate real-time data processing and analysis during experiments. [Extracted from the article]

Published
2023
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12. Phase Transition Dynamics in a Complex Oxide Heterostructure

Author

Zhang, Qingteng, primary, Hu, Guoxiang, additional, Starchenko, Vitalii, additional, Wan, Gang, additional, Dufresne, Eric M., additional, Dong, Yongqi, additional, Liu, Huajun, additional, Zhou, Hua, additional, Jeen, Hyoungjeen, additional, Saritas, Kayahan, additional, Krogel, Jaron T., additional, Reboredo, Fernando A., additional, Lee, Ho Nyung, additional, Sandy, Alec R., additional, Almazan, Irene Calvo, additional, Ganesh, Panchapakesan, additional, and Fong, Dillon D., additional

Published
2022
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13. Advancing AI/ML at the Advanced Photon Source

Author

Benmore, Chris, primary, Bicer, Tekin, additional, Chan, Maria K. Y., additional, Di, Zichao, additional, Gürsoy, Dog˘a, additional, Hwang, Inhui, additional, Kuklev, Nikita, additional, Lin, Dergan, additional, Liu, Zhengchun, additional, Lobach, Ihar, additional, Qiao, Zhi, additional, Rebuffi, Luca, additional, Sharma, Hemant, additional, Shi, Xianbo, additional, Sun, Chengjun, additional, Yao, Yudong, additional, Zhou, Tao, additional, Sandy, Alec, additional, Miceli, Antonino, additional, Sun, Yine, additional, Schwarz, Nicholas, additional, and Cherukara, Mathew J., additional

Published
2022
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16. Evolution of structure and dynamics of thermo-reversible nanoparticle gels—A combined XPCS and rheology study.

Author

Bahadur, Divya, Zhang, Qingteng, Dufresne, Eric M., Grybos, Pawel, Kmon, Piotr, Leheny, Robert L., Maj, Piotr, Narayanan, Suresh, Szczygiel, Robert, Swan, James W., Sandy, Alec, and Ramakrishnan, Subramanian

Subjects
GELATION, LIGHT beating spectroscopy, RHEOLOGY, COLLOIDS, DYNAMICS
Abstract

A combined X-ray photon correlation spectroscopy and rheology study is carried out to capture the evolution of structure, fast particle-scale dynamics, and moduli (elastic and loss) at early times of gel formation near the fluid–gel boundary of a suspension of nanoparticles. The system is comprised of moderately concentrated suspensions of octadecyl silica in decalin (ϕ = 0.2) undergoing thermoreversible gelation. Near the gel boundary, the rate of gel formation is very sensitive to changes in attraction strength. However, we find that at different attraction strengths, the system goes through identical intermediate states of microscopic and macroscopic behavior, even though the absolute time needed to form a gel varies by orders of magnitude. We identify a single dimensionless time parameter, tw/tg, where tw is the wait time following the quench and tg is the rheologically determined gel time, that captures the similarity in gel formation at a range of attraction strengths. Following a temperature quench below the gel boundary, the system is initially fluidlike and forms diffusive clusters (∼8.5 times the particle diameter). After a lag-time, tL, clusters aggregate to form a network like structure which is characterized by the onset of mechanical rigidity and a rapid growth in microscopic relaxation times. At tg, the Baxter parameter obtained from adhesive hard sphere fits of the structure factor attains a constant value corresponding to the theoretical percolation boundary, thus demonstrating that gelation is percolation driven. [ABSTRACT FROM AUTHOR]

Published
2019
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19. Structure, function, and self-assembly of single network gyroid (I[4.sub.1]32) photonic crystals in butterfly wing scales

Author

Saranathan, Vinodkumar, Osuji, Chinedum O., Mochrie, Simon G.J., Noh, Heeso, Narayanan, Suresh, Sandy, Alec, Dufresne, Eric R., and Prum, Richard O.

Subjects
Chitin -- Chemical properties, Butterflies -- Physiological aspects, Biomimetics -- Research, Photonics -- Research, Wings (Animal) -- Properties, Science and technology
Abstract

Complex three-dimensional biophotonic nanostructures produce the vivid structural colors of many butterfly wing scales, but their exact nanoscale organization is uncertain. We used small angle X-ray scattering (SAXS) on single scales to characterize the 3D photonic nanostructures of five butterfly species from two families (Papilionidae, Lycaenidae). We identify these chitin and air nanostructures as single network gyroid (I[4.sub.1]32) photonic crystals. We describe their optical function from SAXS data and photonic band-gap modeling. Butterflies apparently grow these gyroid nanostructures by exploiting the self-organizing physical dynamics of biological lipid-bilayer membranes. These butterfly photonic nanostructures initially develop within scale cells as a core-shell double gyroid (la3d), as seen in block-copolymer systems, with a pentacontinuous volume comprised of extracellular space, cell plasma membrane, cellular cytoplasm, smooth endoplasmic reticulum (SER) membrane, and intra-SER lumen. This double gyroid nanostructure is subsequently transformed into a single gyroid network through the deposition of chitin in the extracellular space and the degeneration of the rest of the cell. The butterflies develop the thermodynamically favored double gyroid precursors as a route to the optically more efficient single gyroid nanostructures. Current approaches to photonic crystal engineering also aim to produce single gyroid motifs. The biologically derived photonic nanostructures characterized here may offer a convenient template for producing optical devices based on biomimicry or direct dielectric infiltration. biological meta-materials | organismal color | biomimetics | biological cubic mesophases doi/ 10.1073/pnas.0909616107

Published
2010

20. Sample and Detector Positioning Instruments for the Wide Angle XPCS End Station at 8-ID-E, a Feature Beamline for the APS Upgrade

Author

Wakefield, Kevin, Bean, Sunil, Capatina, Daniela, Dufresne, Eric, Fisher, Michael, Highland, Matthew, Narayanan, Suresh, Sandy, Alec, and Ziegler, Raymond

Subjects
Beamlines and front ends, Accelerator Physics
Abstract

The X-ray Photon Correlation Spectroscopy (XPCS) beamline at the Advanced Photon Source (APS) has been selected as one of the nine feature beamlines being de-signed to take advantage of the increase in coherent flux provided by the APS Upgrade. The 8-ID-E enclosure at the beamline will have a dedicated instrument for per-forming Wide Angle XPCS (WA-XPCS) measurements across a range of length and time scales. The instrument will feature a high-stability 6-circle diffractometer, a moveable Long Distance Detector Positioner (LDDP) for positioning a large pixel array detector, and a removable flight path assembly. For intermediate sample to detector distances of 1.5 to 2 meters, a large pixel array detector will be positioned on the diffractometer detector arm. For longer sample to detector distances up to 4 meters, an horizontal scattering geometry will be utilized based on the LDDP to position a second large pixel array detector. The LDDP will consist of a large granite base on which sits a combination of motorized stages. The base will sit on air casters that allow the LDDP to be coarsely posi-tioned manually within the enclosure. Final positioning of the detector will be achieved with the mounted stages. The spatial relationship between the sample and the free moving LDDP will be monitored using a laser tracking system. A moveable flight path will be supported by the diffractometer arm and a mobile floor support to mini-mize air scattering while using the LDDP. The WA-XPCS instrument has been designed with users and beamline staff in mind and will allow them to efficiently utilize the highly enhanced coherent beam provided by the APS Upgrade., Proceedings of the 11th Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation, MEDSI2020, Chicago, IL, USA

Published
2021
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21. pyXPCSviewer: an open-source interactive tool for X-ray photon correlation spectroscopy visualization and analysis.

Author

Miaoqi Chu, Li, Jeffrey, Qingteng Zhang, Zhang Jiang, Dufresne, Eric M., Sandy, Alec, Narayanan, Suresh, and Schwarz, Nicholas

Subjects
LIGHT beating spectroscopy, GRAPHICAL user interfaces, X-rays, VISUALIZATION, SYNCHROTRONS, DATA structures
Abstract

pyXPCSviewer, a Python-based graphical user interface that is deployed at beamline 8-ID-I of the Advanced Photon Source for interactive visualization of XPCS results, is introduced. pyXPCSviewer parses rich X-ray photon correlation spectroscopy (XPCS) results into independent PyQt widgets that are both interactive and easy to maintain. pyXPCSviewer is open-source and is open to customization by the XPCS community for ingestion of diversified data structures and inclusion of novel XPCS techniques, both of which are growing demands particularly with the dawn of near-diffraction-limited synchrotron sources and their dedicated XPCS beamlines. [ABSTRACT FROM AUTHOR]

Published
2022
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22. 20 µs-resolved high-throughput X-ray photon correlation spectroscopy on a 500k pixel detector enabled by data-management workflow

Author

Zhang, Qingteng, primary, Dufresne, Eric M., additional, Nakaye, Yasukazu, additional, Jemian, Pete R., additional, Sakumura, Takuto, additional, Sakuma, Yasutaka, additional, Ferrara, Joseph D., additional, Maj, Piotr, additional, Hassan, Asra, additional, Bahadur, Divya, additional, Ramakrishnan, Subramanian, additional, Khan, Faisal, additional, Veseli, Sinisa, additional, Sandy, Alec R., additional, Schwarz, Nicholas, additional, and Narayanan, Suresh, additional

Published
2021
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27. Mechanical Conversion of a Vertically Reflecting Artificial Channel-cut Monochromator to Horizontally Reflecting

Author

Kearney, Steven, Dufresne, Eric, Narayanan, Suresh, Sandy, Alec, and Shu, Deming

Subjects
Beamlines, Accelerator Physics
Abstract

The mechanical conversion of a high-resolution artificial channel-cut monochromator (ACCM) from a vertically reflecting orientation to a horizontally reflecting orientation is presented. The ACCM was originally commissioned for the 8-ID-I beamline at the Advanced Photon Source (APS), Argonne National Laboratory [1, 2]. The ACCM was intentionally designed at commission to have the potential to be reoriented to the horizontal direction. After nearly a decade of operation in the vertical orientation the ACCM was rotated to the horizontal orientation. The details of the design which allowed this conversion and the preparation steps needed to assure the continued performance of the ACCM will be discussed., Proceedings of the Mechanical Eng.~Design of Synchrotron Radiation Equipment and Instrumentation, MEDSI2018, Paris, France

Published
2018
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34. Hard-sphere-like dynamics in highly concentrated alpha-crystallin suspensions

Author

Vodnala, Preeti, primary, Karunaratne, Nuwan, additional, Lurio, Laurence, additional, Thurston, George M., additional, Vega, Michael, additional, Gaillard, Elizabeth, additional, Narayanan, Suresh, additional, Sandy, Alec, additional, Zhang, Qingteng, additional, Dufresne, Eric M., additional, Foffi, Giuseppe, additional, Grybos, Pawel, additional, Kmon, Piotr, additional, Maj, Piotr, additional, and Szczygiel, Robert, additional

Published
2018
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37. Dynamic Scaling of Colloidal Gel Formation at Intermediate Concentrations

Author

Zhang, Qingteng, primary, Bahadur, Divya, additional, Dufresne, Eric M., additional, Grybos, Pawel, additional, Kmon, Piotr, additional, Leheny, Robert L., additional, Maj, Piotr, additional, Narayanan, Suresh, additional, Szczygiel, Robert, additional, Ramakrishnan, Subramanian, additional, and Sandy, Alec, additional

Published
2017
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38. Thermal Fluctuations of Ferroelectric Nanodomains in a Ferroelectric-Dielectric PbTiO3/SrTiO3 Superlattice

Author

Zhang, Qingteng, primary, Dufresne, Eric M., additional, Chen, Pice, additional, Park, Joonkyu, additional, Cosgriff, Margaret P., additional, Yusuf, Mohammed, additional, Dong, Yongqi, additional, Fong, Dillon D., additional, Zhou, Hua, additional, Cai, Zhonghou, additional, Harder, Ross J., additional, Callori, Sara J., additional, Dawber, Matthew, additional, Evans, Paul G., additional, and Sandy, Alec R., additional

Published
2017
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41. First experimental feasibility study of VIPIC: a custom-made detector for X-ray speckle measurements

Author

Rumaiz, Abdul K., primary, Siddons, D. Peter, additional, Deptuch, Grzegorz, additional, Maj, Piotr, additional, Kuczewski, Anthony J., additional, Carini, Gabriella A., additional, Narayanan, Suresh, additional, Dufresne, Eric M., additional, Sandy, Alec, additional, Bradford, Robert, additional, Fluerasu, Andrei, additional, and Sutton, Mark, additional

Published
2016
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42. Anomalous phase transitions in soft colloid-polymer binary mixtures

Author

Basu, Jaydeep, Kandar, Ajoy, Narayanan, Suresh, and Sandy, Alec

Subjects
Physics
Abstract

We have shown earlier [1] that these PGNPs resemble star polymers or spherical brushes in terms of their morphology in the melt. However, these particles show dynamics in melt which is quite different from other soft colloidal particles. Since most of the work on soft colloidal particles have been performed in solutions we have now explored the phase behavior of the PGNPs in good solvent using microscopic structural and dynamical measurements on binary mixtures of homopolymers and soft colloids consisting of polymer grafted nanoparticles. We observe anomalous structural and dynamical phase transitions of these binary mixtures, including appearance of spontaneous orientational alignment and logarithmic structural relaxations, as a function of added homopolymers of different molecular weights. Our experiments points to the possibility of exploiting the phase space in density and homopolymer size, of such hybrid systems, to create new materials with unique properties.

Published
2012

45. Radiation damage limits to XPCS studies of protein dynamics

Author

Vodnala, Preeti, primary, Karunaratne, Nuwan, additional, Bera, Sambhunath, additional, Lurio, Laurence, additional, Thurston, George M., additional, Karonis, Nick, additional, Winans, John, additional, Sandy, Alec, additional, Narayanan, Suresh, additional, Yasui, Linda, additional, Gaillard, Elizabeth, additional, and Karumanchi, Kalyan, additional

Published
2016
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