Anisotropic Raman scattering and lattice orientation identification of 2M-WS2

Sabin Gautam; Sougata Mardanya; Joseph McBride; A K M Manjur Hossain; Qian Yang; Wenyong Wang; John Ackerman; Brian M. Leonard; Sugata Chowdhury; Jifa Tian

arXiv · 2501.00945

Anisotropic Raman scattering and lattice orientation identification of 2M-WS2

Sabin Gautam·Sougata Mardanya·Joseph McBride·A K M Manjur Hossain·Qian Yang·Wenyong Wang·John Ackerman·Brian M. Leonard·Sugata Chowdhury·Jifa Tian

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Abstract

Anisotropic materials with low symmetries hold significant promise for next-generation electronic and quantum devices. 2M-WS2, a candidate for topological superconductivity, has garnered considerable interest. However, a comprehensive understanding of how its anisotropic features contribute to unconventional superconductivity, along with a simple, reliable method to identify its crystal orientation, remains elusive. Here, we combine theoretical and experimental approaches to investigate angle- and polarization-dependent anisotropic Raman modes of 2M-WS2. Through first-principles calculations, we predict and analyze phonon dispersion and lattice vibrations of all Raman modes in 2M-WS2. We establish a direct correlation between their anisotropic Raman spectra and high-resolution transmission electron microscopy images. Finally, we demonstrate that anisotropic Raman spectroscopy can accurately determine the crystal orientation and twist angle between two stacked 2M-WS2 layers. Our findings provide insights into the electron-phonon coupling and anisotropic properties of 2M-WS2, paving the way for the use of anisotropic materials in advanced electronic and quantum devices.

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Sabin Gautam, Sougata Mardanya, Joseph McBride, A K M Manjur Hossain, Qian Yang, Wenyong Wang, John Ackerman, Brian M. Leonard, Sugata Chowdhury, Jifa Tian. 2025-01-01. Anisotropic Raman scattering and lattice orientation identification of 2M-WS2. https://arxiv.org/abs/2501.00945

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