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arXiv · 1207.0073

Anomalous thermal expansion of Sb$_2$Te$_3$ topological insulator

P. Dutta·D. Bhoi·A. Midya·N. Khan·P. Mandal·S. Shanmukharao Samatham·V. Ganesan
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Abstract

We have investigated the temperature dependence of the linear thermal expansion along the hexagonal c axis ($\Delta L$), in-plane resistivity ($\rho$), and specific heat ($C_p$) of the topological insulator Sb$_2$Te$_3$ single crystal. $\Delta L$ exhibits a clear anomaly in the temperature region 204-236 K. The coefficient of linear thermal expansion $\alpha$ decreases rapidly above 204 K, passes through a deep minimum at around 225 K and then increases abruptly in the region 225-236 K. $\alpha$ is negative in the interval 221-228 K. The temperature dependence of both $\alpha$ and $C_p$ can be described well by the Debye model from 2 to 290 K, excluding the region around the anomaly in $\alpha$.

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P. Dutta, D. Bhoi, A. Midya, N. Khan, P. Mandal, S. Shanmukharao Samatham, V. Ganesan. 2012-06-30. Anomalous thermal expansion of Sb$_2$Te$_3$ topological insulator. https://doi.org/10.1063/1.4730390

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