Observing a previously hidden structural-phase transition onset through heteroepitaxial cap response
[2];
[6];
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, 200433 Shanghai, China,
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831,
- Center for Nanophase Materials Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831,
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, 200433 Shanghai, China,, Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, 200433 Shanghai, China,
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, 200433 Shanghai, China,, Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, 200433 Shanghai, China,, Collaborative Innovation Center of Advanced Microstructures, 210093 Nanjing, China,
- Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70808
Characterization of the onset of a phase transition is often challenging due to the fluctuations of the correlation length scales of the order parameters. This is especially true for second-order structural-phase transition due to minute changes involved in the relevant lattice constants. A classic example is the cubic-to-tetragonal second-order phase transition in SrTiO3 (STO), which is so subtle that it is still unresolved. Here, we demonstrate an approach to resolve this issue by epitaxially grown rhombohedral La0.7Sr0.3MnO3 (LSMO) thin films on the cubic STO (100) substrate. The shear strain induced nanotwinning waves in the LSMO film are extremely sensitive to the cubic-to-tetragonal structural-phase transitions of the STO substrate. Upon cooling from room temperature, the development of the nanotwinning waves is spatially inhomogeneous. Untwinned, atomically flat domains, ranging in size from 100 to 300 nm, start to appear randomly in the twinned phase between 265 and 175 K. At ~139 K, the untwinned, atomically flat domains start to grow rapidly into micrometer scale and finally become dominant at ~108 K. These results indicate that the low-temperature tetragonal precursor phase of STO has already nucleated at 265 K, significantly higher than the critical temperature of STO (~105 K). Our work paves a pathway to visualize the onset stages of structural-phase transitions that are too subtle to be observed using direct-imaging methods.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Louisiana State Univ., Baton Rouge, LA (United States)
- Sponsoring Organization:
- USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division; National Key Research and Development Program of China; National Natural Science Foundation of China (NSFC); Shanghai Municipal Natural Science Foundation
- Grant/Contract Number:
- SC0002136; AC05-00OR22725; 2016YFA0300702; 2014CB921104; 11504053; 18JC1411400; 18ZR1403200; 18XD1400600; 17XD1400400
- OSTI ID:
- 1495315
- Alternate ID(s):
- OSTI ID: 1818758
- Journal Information:
- Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Vol. 116 Journal Issue: 10; ISSN 0027-8424
- Publisher:
- Proceedings of the National Academy of SciencesCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures
Unexpected Intermediate State Photoinduced in the Metal-Insulator Transition of Submicrometer Phase-Separated Manganites