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Title: Prediction and Experimental Evidence for Thermodynamically Stable Charged Orbital Domain Walls

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1163647
Report Number(s):
BNL-106227-2014-JA
R&D Project: PO011; KC0201060
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: PHYSICAL REVIEW X; Journal Volume: 4; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Li Q., Wilkins S., Gray, K. E., Fernandez, M. Garcia, Rosenkranz, S., Zheng, H., and Mitchell, J. F. Prediction and Experimental Evidence for Thermodynamically Stable Charged Orbital Domain Walls. United States: N. p., 2014. Web. doi:10.1103/PhysRevX.4.031028.
Li Q., Wilkins S., Gray, K. E., Fernandez, M. Garcia, Rosenkranz, S., Zheng, H., & Mitchell, J. F. Prediction and Experimental Evidence for Thermodynamically Stable Charged Orbital Domain Walls. United States. doi:10.1103/PhysRevX.4.031028.
Li Q., Wilkins S., Gray, K. E., Fernandez, M. Garcia, Rosenkranz, S., Zheng, H., and Mitchell, J. F. Mon . "Prediction and Experimental Evidence for Thermodynamically Stable Charged Orbital Domain Walls". United States. doi:10.1103/PhysRevX.4.031028.
@article{osti_1163647,
title = {Prediction and Experimental Evidence for Thermodynamically Stable Charged Orbital Domain Walls},
author = {Li Q. and Wilkins S. and Gray, K. E. and Fernandez, M. Garcia and Rosenkranz, S. and Zheng, H. and Mitchell, J. F.},
abstractNote = {},
doi = {10.1103/PhysRevX.4.031028},
journal = {PHYSICAL REVIEW X},
number = 3,
volume = 4,
place = {United States},
year = {Mon Aug 18 00:00:00 EDT 2014},
month = {Mon Aug 18 00:00:00 EDT 2014}
}
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  • On theoretical grounds, we show that orbital domain walls (ODWs), which are known to exist in the charge and orbital ordered layered manganite LaSr 2Mn 2O 7, should be partially charged as a result of competition between orbital-induced strain and Coulomb repulsion. Furthermore, this unexpected result provides the necessary condition for the known thermodynamic stability of these ODWs, which are unlike the more typical domain walls that arise only from an external field. We offer experimental data consistent with this theoretical framework through a combined transport and x-ray-diffraction study. In particular, our transport data on this charge and orbital orderedmore » manganite exhibit abrupt transformations to higher conductance at a threshold electric field. As transport phenomena closely resemble effects found for sliding charge-density waves (SCDWs) in pseudo-one-dimensional (1D) materials, a SCDW along such pseudo-1D ODWs provides a natural explanation of our data. Importantly, x-ray-diffraction data eliminate heating and melting of charge order as tenable alternative explanations of our data.« less
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