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arXiv · 1703.06904

Reentrant Phase Diagram of $\rm{Yb_2Ti_2O_7}$ in $\langle 111 \rangle$ Magnetic Field

A. Scheie·J. Kindervater·S. Säubert·C. Duvinage·C. Pfleiderer·H. J. Changlani·S. Zhang·L. Harriger·K. Arpino·S. M. Koohpayeh·O. Tchernyshyov·C. Broholm
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Abstract

We present a magnetic phase diagram of rare-earth pyrochlore $\rm{Yb_2Ti_2O_7}$ in a $\langle 111 \rangle$ magnetic field. Using heat capacity, magnetization, and neutron scattering data, we show an unusual field-dependence of a first-order phase boundary, wherein a small applied field increases the ordering temperature. The zero-field ground state has ferromagnetic domains, while the spins polarize along $\langle 111 \rangle$ above 0.65T. A classical Monte Carlo analysis of published Hamiltonians does account for the critical field in the low T limit. However, this analysis fails to account for the large bulge in the reentrant phase diagram, suggesting that either long-range interactions or quantum fluctuations govern low field properties.

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A. Scheie, J. Kindervater, S. Säubert, C. Duvinage, C. Pfleiderer, H. J. Changlani, S. Zhang, L. Harriger, K. Arpino, S. M. Koohpayeh, O. Tchernyshyov, C. Broholm. 2017-06-22. Reentrant Phase Diagram of $\rm{Yb_2Ti_2O_7}$ in $\langle 111 \rangle$ Magnetic Field. https://doi.org/10.1103/physrevlett.119.127201

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