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arXiv · 2208.01904

Significant thermal Hall effect in the 3$d$ cobalt Kitaev system $Na_2Co_2TeO_6$

Heejun Yang·Chaebin Kim·Ysun Choi·Jun Han Lee·Gaoting Lin·Jie Ma·Marie Kratochvílová·Petr Proschek·Eun-Gook Moon·Ki Hoon Lee·Yoon Seok Oh·Je-Geun Park
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Abstract

Kitaev physics has recently attracted attention in condensed matter for its anticipated novel quantum spin liquid state. The thermal transport measurement is crucial for probing the novel features of charge-neutral quasiparticles. In this letter, we report a significant thermal Hall effect in $Na_2Co_2TeO_6$ (NCTO), a Kitaev quantum spin liquid candidate, when the magnetic field is applied along the out-of-plane direction of the honeycomb plane. The thermal conductivity ($\kappa_{xx}$) and thermal Hall conductivity ($\kappa_{xy}$) in NCTO reveal distinct magnetic field dependences below and above the Neel temperature ($T_N$) of 27 K. For $T>T_N$, $\kappa_{xx}$ has a monotonic decrease in the field dependence, while $\kappa_{xy}$ persists up to $T^*$ = 150 K. On the other hand, both $\kappa_{xx}$ and $\kappa_{xy}$ exhibit complex field dependence for $T<T_N$.

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Heejun Yang, Chaebin Kim, Ysun Choi, Jun Han Lee, Gaoting Lin, Jie Ma, Marie Kratochvílová, Petr Proschek, Eun-Gook Moon, Ki Hoon Lee, Yoon Seok Oh, Je-Geun Park. 2022-08-03. Significant thermal Hall effect in the 3$d$ cobalt Kitaev system $Na_2Co_2TeO_6$. https://doi.org/10.1103/physrevb.106.l081116

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