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arXiv · 1608.07401

Thermal Hall effect in a phonon-glass Ba$_3$CuSb$_2$O$_9$

Kaori Sugii·Masaaki Shimozawa·Daiki Watanabe·Yoshitaka Suzuki·Mario Halim·Motoi Kimata·Yosuke Matsumoto·Satoru Nakatsuji·Minoru Yamashita
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Abstract

A distinct thermal Hall signal is observed in a quantum spin liquid candidate Ba$_3$CuSb$_2$O$_9$. The transverse thermal conduction shows a power-law temperature dependence below 40 K where a spin gap opens. We suggest that, through the very low longitudinal thermal conductivity and the thermal Hall signals, a phonon Hall effect is induced by strong phonon scatterings by orphan Cu$^{2+}$ spins formed in random domains of Cu$^{2+}$-Sb$^{5+}$ dumbbells.

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Kaori Sugii, Masaaki Shimozawa, Daiki Watanabe, Yoshitaka Suzuki, Mario Halim, Motoi Kimata, Yosuke Matsumoto, Satoru Nakatsuji, Minoru Yamashita. 2016-08-26. Thermal Hall effect in a phonon-glass Ba$_3$CuSb$_2$O$_9$. https://doi.org/10.1103/physrevlett.118.145902

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