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arXiv · 1807.11118

Spin Thermal Hall Conductivity of a Kagomé Antiferromagnet

Hayato Doki·Masatoshi Akazawa·Hyun-Yong Lee·Jung Hoon Han·Kaori Sugii·Masaaki Shimozawa·Naoki Kawashima·Migaku Oda·Hiroyuki Yoshida·Minoru Yamashita
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Abstract

A clear thermal Hall signal ($κ_{xy}$) was observed in the spin liquid phase of the $S=1/2$ kagomé antiferromagnet Ca kapellasite (CaCu$_3$(OH)$_6$Cl$_2\cdot 0.6$H$_2$O). We found that $κ_{xy}$ is well reproduced, both qualitatively and quantitatively, using the Schwinger-boson mean-field theory with the Dzyaloshinskii--Moriya interaction of $D/J \sim 0.1$. In particular, $κ_{xy}$ values of Ca kapellasite and those of another kagomé antiferromagnet, volborthite, converge to one single curve in simulations modeled using Schwinger bosons, indicating a common temperature dependence of $κ_{xy}$ for the spins of a kagomé antiferromagnet.

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Hayato Doki, Masatoshi Akazawa, Hyun-Yong Lee, Jung Hoon Han, Kaori Sugii, Masaaki Shimozawa, Naoki Kawashima, Migaku Oda, Hiroyuki Yoshida, Minoru Yamashita. 2018-07-29. Spin Thermal Hall Conductivity of a Kagomé Antiferromagnet. https://doi.org/10.1103/physrevlett.121.097203

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