Understanding Reentrance in Frustrated Magnets: The Case of the Er2Sn2O7 Pyrochlore

Published

December 30, 2021

Author(s)

D. R. Yahne, D. Pereira, L. D. Jaubert, L. D. Sanjeewa, M. Powell, J. W. Kolis, Guangyong Xu, M. Enjalran, M. J. Gingras, K. A. Ross

Abstract

Reentrance is a recurring theme found in a variety of physical systems, including spin glasses and black hole thermodynamics, yet the underlying microscopic mechanisms leading to it are rarely investigated in detail. Here we provide a detailed characterization and mechanistic understanding of reentrance in the strongly frustrated pyrochlore Er₂Sn₂O₇. Taking advantage of the recent advance in rare-earth stannate single crystal synthesis, we use heat capacity measurements to show that Er₂Sn₂O₇ has multiple instances of reentrance in its B-T phase diagram for magnetic fields along three high symmetry directions ([100], [110], and [111]). Through classical Monte Carlo simulations, mean field theory and classical linear spin-wave expansion, we propose that the origins of the multiple instances of reentrance in Er₂Sn₂O₇ are linked to T = 0 multi-phase competition, either induced by the applied field or the inherent proximity to a competing zero-field antiferromagnetic phase, depending on the instance. The ground state phase competition enhances thermal fluctuations that entropically stabilize the ordered phase, leading to increased transition temperatures for certain field values and thus reentrance. Our work represents a detailed examination into the mechanisms responsible for reentrance in frustrated magnets and which may serve as a guide for other reentrant phenomena in physics.

Citation

Physical Review Letters

Volume

127

Issue

27

Pub Type

Journals

Keywords

neutron scattering, frustrated magnet, pyrochlore, reentrance

Citation

Yahne, D. , Pereira, D. , Jaubert, L. , Sanjeewa, L. , Powell, M. , Kolis, J. , Xu, G. , Enjalran, M. , Gingras, M. and Ross, K. (2021), Understanding Reentrance in Frustrated Magnets: The Case of the Er₂Sn₂O₇ Pyrochlore, Physical Review Letters (Accessed April 24, 2024)