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arXiv · 1112.1608

Thermal Expansion Coefficients of Bi$_2$Se$_3$ and Sb$_2$Te$_3$ Crystals from 10 K to 270 K

X. Chen·H. D. Zhou·A. Kiswandhi·I. Miotkowski·Y. P. Chen·P. A. Sharma·A. L. Lima Sharma·M. A. Hekmaty·D. Smirnov·Z. Jiang
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Abstract

Lattice constant of Bi$_2$Se$_3$ and Sb$_2$Te$_3$ crystals is determined by X-ray powder diffraction measurement in a wide temperature range. Linear thermal expansion coefficients ($α$) of the crystals are extracted, and considerable anisotropy between $α_\parallel$ and $α_\perp$ is observed. The low temperature values of $α$ can be fit well by the Debye model, while an anomalous behavior at above 150 K is evidenced and explained. Grüneisen parameters of the materials are also estimated at room temperature.

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X. Chen, H. D. Zhou, A. Kiswandhi, I. Miotkowski, Y. P. Chen, P. A. Sharma, A. L. Lima Sharma, M. A. Hekmaty, D. Smirnov, Z. Jiang. 2011-12-30. Thermal Expansion Coefficients of Bi$_2$Se$_3$ and Sb$_2$Te$_3$ Crystals from 10 K to 270 K. https://doi.org/10.1063/1.3672198

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