Abstract
We show that a polar, pseudo-Jahn-Teller instability exists for the underbonded rare-earth -site cations in the quadruple perovskite , which leads to the spontaneous formation of a dipolar glass. This observation alone expands the applicability of pseudo-Jahn-Teller physics in perovskite-derived materials, for which it is typically confined to -site cations. We demonstrate that the dipolar glass order parameter is coupled to a ferrimagnetic order parameter via strain, leading to a first order magnetostructural phase transition that can be tuned by magnetic field. This phenomenology may emerge in a broad range of perovskite-derived materials in which -site cation ordering and octahedral tilting are mutually tied to meet the criteria of structural stability.
- Received 6 April 2020
- Revised 15 May 2020
- Accepted 28 July 2020
DOI:https://doi.org/10.1103/PhysRevLett.125.097601
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