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arXiv · 2301.00350

Anisotropic Light-Matter Interactions in Single Crystal Topological Insulator Bismuth Selenide

Divya Rawat·Aditya Singh·Niraj Kumar Singh·Ajay Soni
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Abstract

Anisotropy of light-matter interactions in materials give remarkable information about the phonons and their interactions with electrons. We report the angle-resolved polarized Raman spectroscopy of single-crystal of Bi2Se3 to obtain the elements of Raman tensor for understanding the strength of polarization along different crystallographic orientations. Intensity variation in the polar plots corresponding to E_g^1 ~ 37 cm-1, A_1g^1 ~71 cm-1, E_g^2 ~ 130 cm-1, and A_1g^2 ~ 173 cm-1 suggests the higher differential polarizability along cross-plane (bc-plane). The polar patterns and the differences in elements of the Raman tensor provides the evidence of the fundamental electron-phonon and anisotropic light matter interactions in Bi2Se3.

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Divya Rawat, Aditya Singh, Niraj Kumar Singh, Ajay Soni. 2023-01-01. Anisotropic Light-Matter Interactions in Single Crystal Topological Insulator Bismuth Selenide. https://doi.org/10.1103/physrevb.107.155203

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