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arXiv · 2006.09775

Field evolution of the spin-liquid candidate YbMgGaO$_4$

Sebastian Bachus·Ilia A. Iakovlev·Yuesheng Li·Andreas Wörl·Yoshifumi Tokiwa·Langsheng Ling·Qingming Zhang·Vladimir V. Mazurenko·Philipp Gegenwart·Alexander A. Tsirlin
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Abstract

We report magnetization, heat capacity, thermal expansion, and magnetostriction measurements down to millikelvin temperatures on the triangular antiferromagnet YbMgGaO$_4$. Our data exclude the formation of the distinct $\frac13$ plateau phase observed in other triangular antiferromagnets, but reveal plateaulike features in second derivatives of the free energy, magnetic susceptibility and specific heat, at $\mu_0H$ = 1.0 - 2.5 T for $H\parallel{}c$ and 2 - 5 T for $H\perp{}c$. Using Monte-Carlo simulations of a realistic spin Hamiltonian, we ascribe these features to nonmonotonic changes in the magnetization and the $\frac12$ plateau that is smeared out by the random distribution of exchange couplings in YbMgGaO$_4$.

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Sebastian Bachus, Ilia A. Iakovlev, Yuesheng Li, Andreas Wörl, Yoshifumi Tokiwa, Langsheng Ling, Qingming Zhang, Vladimir V. Mazurenko, Philipp Gegenwart, Alexander A. Tsirlin. 2020-06-17. Field evolution of the spin-liquid candidate YbMgGaO$_4$. https://doi.org/10.1103/physrevb.102.104433

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