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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Long-Range Order in the Dipolar XY Antiferromagnet Er_{2}Sn_{2}O_{7}
1Laboratoire Léon Brillouin, CEA, CNRS, Université Paris-Saclay, CE-Saclay, 91191 Gif-sur-Yvette, France.
Physical Review Letters
|December 9, 2017
Summary
Erbium stannate (Er2Sn2O7) exhibits a second-order magnetic transition to the Palmer-Chalker state at 108 mK, confirming its role as a dipolar XY pyrochlore antiferromagnet. This finding resolves long-standing questions about its magnetic behavior and potential as a spin-liquid candidate.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Quantum Materials
Background:
- Rare-earth pyrochlores are known for magnetic frustration.
- Erbium stannate (Er2Sn2O7) was predicted to have a first-order transition to an ordered state, but this remained unobserved.
- Its status as a spin-liquid candidate was uncertain.
Purpose of the Study:
- To investigate the magnetic ordering in Er2Sn2O7.
- To determine the nature of the magnetic transition.
- To clarify the magnetic properties and phase diagram of this frustrated pyrochlore.
Main Methods:
- Neutron scattering experiments were performed.
- Magnetization measurements were conducted.
- Spin-wave analysis was used to refine exchange parameters.
Main Results:
- A second-order phase transition to the Palmer-Chalker ordered state was observed at 108 mK.
- Successful observation required careful sample thermalization.
- A gap opened in excitations at the transition, alongside a quasielastic signal.
- Exchange parameters confirmed Er2Sn2O7 as a dipolar XY pyrochlore antiferromagnet.
Conclusions:
- Er2Sn2O7 is a realization of the dipolar XY pyrochlore antiferromagnet.
- The transition is second-order, contrary to previous theoretical predictions.
- Enhanced fluctuations due to competing phases and strong XY anisotropy may explain the low ordering temperature and observed dynamics.
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