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arXiv · 2109.01420

Growth and characterization of high-quality single-crystalline SnTe retaining cubic symmetry down to the lowest temperature studied

Abstract

SnTe, an archetypical topological crystalline insulator, often shows a transition from a highly symmetric cubic phase to a rhombohedral structure at low temperatures. In order to achieve the highly symmetric cubic phase at low temperatures suitable for quantum behaviour, we have employed the modified Bridgman method to grow a high-quality single-crystalline sample of SnTe. Analysis of the crystal structure using Laue diffraction and rocking curve measurements show a very high degree of single crystallinity of the sample. Resistivity and the specific heat data do not show the signature of structural transition down to the lowest temperature studied. The magnetic susceptibility shows diamagnetic behaviour. All these properties manifest the behaviour of a typical bulk semiconductor with conducting surface states as expected in a topological material. Detailed powder x-ray diffraction measurements show cubic structure in the whole temperature range studied.

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Ayanesh Maiti, Ankita Singh, Kartik K. Iyer, Arumugam Thamizhavel. 2021-09-03. Growth and characterization of high-quality single-crystalline SnTe retaining cubic symmetry down to the lowest temperature studied. https://doi.org/10.1063/5.0086644

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