Ground state selection under pressure in the quantum pyrochlore magnet Yb2Ti2O7
E Kermarrec1,2,3, J Gaudet2, K Fritsch4
1Laboratoire de Physique des Solides, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay Cedex 91405, France.
Nature Communications
|March 16, 2017
Summary
Researchers investigated Ytterbium-2,Titanium-2,Oxide-7 (Yb2Ti2O7) under pressure. Applying pressure revealed a transition from a disordered state to a splayed ferromagnetic state, clarifying its low-temperature magnetic behavior.
Area of Science:
- Condensed matter physics
- Quantum magnetism
Background:
- Quantum spin liquids are exotic states of matter with quantum entanglement and no broken symmetry.
- Rare-earth pyrochlores like Ho2Ti2O7 and Dy2Ti2O7 exhibit classical spin ice states with magnetic monopoles.
- Yb2Ti2O7 is a candidate for quantum spin ice, but its low-temperature magnetic order remains controversial.
Purpose of the Study:
- To elucidate the low-temperature magnetic behavior of the quantum spin ice candidate Yb2Ti2O7.
- To investigate the role of pressure in tuning the magnetic properties of Yb2Ti2O7.
Main Methods:
- Neutron diffraction
- Muon spin relaxation
- Application of external pressure to a stoichiometric Yb2Ti2O7 sample.
Main Results:
- Evidence of a pressure-induced magnetic transition in Yb2Ti2O7.
- The transition is from a disordered, non-magnetic ground state to a splayed ferromagnetic ground state.
- Pressure is identified as a critical factor in understanding Yb2Ti2O7's low-temperature behavior.
Conclusions:
- The low-temperature magnetic properties of Yb2Ti2O7 are sensitive to pressure.
- Under pressure, Yb2Ti2O7 transitions into a splayed ferromagnetic state.
- This resolves long-standing controversies regarding its magnetic order.
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