1
|
Frazer TD, Zhu Y, Cai Z, Walko DA, Adamo C, Schlom DG, Fullerton EE, Evans PG, Hruszkewycz SO, Cao Y, Wen H. Optical transient grating pumped X-ray diffraction microscopy for studying mesoscale structural dynamics. Sci Rep 2021; 11:19322. [PMID: 34588533 PMCID: PMC8481406 DOI: 10.1038/s41598-021-98741-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/14/2021] [Indexed: 11/30/2022] Open
Abstract
A fundamental understanding of materials’ structural dynamics, with fine spatial and temporal control, underpins future developments in electronic and quantum materials. Here, we introduce an optical transient grating pump and focused X-ray diffraction probe technique (TGXD) to examine the structural evolution of materials excited by modulated light with a precisely controlled spatial profile. This method adds spatial resolution and direct structural sensitivity to the established utility of a sinusoidal transient-grating excitation. We demonstrate TGXD using two thin-film samples: epitaxial BiFeO3, which exhibits a photoinduced strain (structural grating) with an amplitude proportional to the optical fluence, and FeRh, which undergoes a magnetostructural phase transformation. In BiFeO3, structural relaxation is location independent, and the strain persists on the order of microseconds, consistent with the optical excitation of long-lived charge carriers. The strain profile of the structural grating in FeRh, in comparison, deviates from the sinusoidal excitation and exhibits both higher-order spatial frequencies and a location-dependent relaxation. The focused X-ray probe provides spatial resolution within the engineered optical excitation profile, resolving the spatiotemporal flow of heat through FeRh locally heated above the phase transition temperature. TGXD successfully characterizes mesoscopic energy transport in functional materials without relying on a specific transport model.
Collapse
Affiliation(s)
- Travis D Frazer
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Yi Zhu
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Zhonghou Cai
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Donald A Walko
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Carolina Adamo
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA
| | - Darrell G Schlom
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA.,Leibniz-Institut Für Kristallzüchtung, Max-Born-Str. 2, 12489, Berlin, Germany
| | - Eric E Fullerton
- Center for Memory and Recording Research, University of California San Diego, La Jolla, CA, 92903, USA
| | - Paul G Evans
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | - Yue Cao
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA.
| | - Haidan Wen
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL, 60439, USA.
| |
Collapse
|
2
|
Shen K, Vignale G. Interacting drift-diffusion theory for photoexcited electron-hole gratings in semiconductor quantum wells. PHYSICAL REVIEW LETTERS 2013; 110:096601. [PMID: 23496734 DOI: 10.1103/physrevlett.110.096601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Indexed: 06/01/2023]
Abstract
Phase-resolved transient grating spectroscopy in semiconductor quantum wells has been shown to be a powerful technique for measuring the electron-hole drag resistivity ρ(eh), which depends on the Coulomb interaction between the carriers. In this Letter we develop the interacting drift-diffusion theory, from which ρ(eh) can be determined, given the measured mobility of an electron-hole grating. From this theory we predict a crossover from a high-excitation-density regime, in which the mobility has the "normal" positive value, to a low-density regime, in which Coulomb drag dominates and the mobility becomes negative. At the crossover point, the mobility of the grating vanishes.
Collapse
Affiliation(s)
- Ka Shen
- Department of Physics and Astronomy, University of Missouri, Columbia, Missouri 65211, USA
| | | |
Collapse
|
3
|
Koralek JD, Yang L, Tibbetts DR, Reno JL, Lilly MP, Orenstein J. Doppler velocimetry of spin and charge currents in the 2D Fermi gas. EPJ WEB OF CONFERENCES 2013. [DOI: 10.1051/epjconf/20134103017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|