Understanding Reentrance in Frustrated Magnets: The Case of the Er_{2}Sn_{2}O_{7} Pyrochlore
D R Yahne1, D Pereira2, L D C Jaubert3
1Department of Physics, Colorado State University, 200 W. Lake Street, Fort Collins, Colorado 80523-1875, USA.
Physical Review Letters
|January 21, 2022
Summary
Reentrance in frustrated magnets like Er2Sn2O7 is explained by soft modes. These modes, driven by phase competition, enhance fluctuations that stabilize ordered phases, causing reentrant magnetic behavior.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Thermodynamics
Background:
- Reentrance describes systems returning to less-ordered states as parameters change.
- The microscopic origins of reentrance are often not fully understood.
- Frustrated magnets provide a complex platform to study such phenomena.
Purpose of the Study:
- To investigate the microscopic mechanism of reentrance in the pyrochlore antiferromagnet Er2Sn2O7.
- To characterize the reentrant behavior in Er2Sn2O7's magnetic phase diagram.
- To provide a theoretical framework for understanding reentrance in frustrated magnetic systems.
Main Methods:
- Single crystal heat capacity measurements.
- Classical Monte Carlo simulations.
- Mean field theory and classical linear spin-wave expansions.
Main Results:
- Er2Sn2O7 exhibits multiple reentrant phases in its magnetic field vs temperature phase diagram.
- Reentrance is linked to soft modes arising from phase competition.
- Soft modes enhance thermal fluctuations, entropically stabilizing ordered phases.
Conclusions:
- The study uncovers the microscopic mechanism behind reentrance in Er2Sn2O7.
- Soft modes and phase competition are key drivers of reentrant behavior.
- This work serves as a model for interpreting reentrance in other physical systems.
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