Thickness dependent Mn valence in La0.7Sr0.3MnO3 thin films
Abstract
The Mn valence in thin film La0.7Sr0.3MnO3 is studied as a function of film thickness in the range of 1-16u.c. Using a combination of bulk and surface sensitive x-ray absorption spectroscopy techniques, the layer-by-layer Mn valence is determined for these film thicknesses. It is found that while the bulk averaged valence hovers around its expected value of 3.3, a significant deviation occurs within several unit cells of the surface and interface, where the surface and interface valence are determined to be 4 and 2.68, respectively. These results are supported by theoretical calculations. The change in valence from the expected bulk value arises from the polar discontinuity at the film-substrate interface.
NSF (DMR-1608656), U.S. Department of Energy DE-SC0016176, US Department of Energy DE-AC02-05CH, National Natural Science Foundation of China (No. 11274060).- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2017
- Bibcode:
- 2017APS..MARP43001T