Effects of rare earth ion size on the stability of the coherent Jahn-Teller distortions in undoped perovskite manganites
| Autor: | Turab Lookman, Peter B. Littlewood, Avadh Saxena, Tsezar F. Seman, A. R. Bishop, K. H. Ahn |
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| Rok vydání: | 2012 |
| Předmět: |
Condensed Matter - Materials Science
Materials science Colossal magnetoresistance Condensed matter physics Strongly Correlated Electrons (cond-mat.str-el) Jahn–Teller effect Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences Condensed Matter Physics Atomic units Symmetry (physics) Electronic Optical and Magnetic Materials Ion Keating model Shear (sheet metal) Condensed Matter - Strongly Correlated Electrons Distortion Condensed Matter::Strongly Correlated Electrons |
| DOI: | 10.48550/arxiv.1208.2304 |
| Popis: | We present a theoretical study on the relation between the size of the rare earth ions, often known as chemical pressure, and the stability of the coherent Jahn-Teller distortions in undoped perovskite manganites. Using a Keating model expressed in terms of atomic scale symmetry modes, we show that there exists a coupling between the uniform shear distortion and the staggered buckling distortion within the Jahn-Teller energy term. It is found that this coupling provides a mechanism by which the coherent Jahn-Teller distortion is more stabilized by smaller rare earth ions. We analyze the appearance of the uniform shear distortion below the Jahn-Teller ordering temperature, estimate the Jahn-Teller ordering temperature and its variation between NdMnO3 and LaMnO3, and obtain the relations between distortions. We find good agreement between theoretical results and experimental data. Comment: 6 figures |
| Databáze: | OpenAIRE |
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