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arXiv · 2009.07757

High Field Magneto-Transport of Mixed Topological Insulators Bi2Se3-xTex (x = 0, 1, 2 & 3)

Deepak Sharma·Yogesh Kumar·P. Kumar·Vipin Nagpal·S. Patnaik·V. P. S. Awana
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Abstract

The article comprises structural, microstructural, and physical properties analysis of Bi2Se3-xTex (x= 0, 1, 2 and 3) mixed topological insulator (MTI) single crystals. All the crystals were grown through a well-optimized solid-state reaction route via the self-flux method. These MTI are well characterized through XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), EDAX (Energy Dispersive spectroscopy), and thereby, the physical properties are analyzed through the RT (Resistance vs temperature) down to 10K as well as the magneto-resistance (MR) measurements (at 5K) in a magnetic field of up to 10 Tesla. The MR drastically varies from x=0 to x=3 in MTI, from a huge 400 percent, it goes down to 20 percent and 5 percent and eventually back to 315 percent. This fascinated behaviour of MR is explained in this article through HLN (Hikami-Larkin-Nagaoka) equation and an additional term. This article not only proposed the mesmerizing behavior of MR in MTI but also explains the reason through competing WAL (Weak Anti-Localization) and WL (Weak Localization) conduction processes.

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Deepak Sharma, Yogesh Kumar, P. Kumar, Vipin Nagpal, S. Patnaik, V. P. S. Awana. 2020-09-16. High Field Magneto-Transport of Mixed Topological Insulators Bi2Se3-xTex (x = 0, 1, 2 & 3). https://doi.org/10.1016/j.ssc.2020.114097

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