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arXiv · 2507.17203

Phonon Dynamics of Topological Quantum Materials

Vivek Kumar
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Abstract

The thesis presents a comprehensive Raman spectroscopic and first-principle density functional theory based investigation of V_(1-x)PS_(3) ; PbTaSe_(2) and 1T-TaS_(2). In V_(1-x)PS_(3),the detection of fractionalized excitations (Majorana fermions) suggests a potential Kitaev spin liquid phase, which becomes more pronounced as dimensionality decreases. Evidence of temperature-driven structural phase transition and topological surface phonons has been detected in PbTaSe_(2). TaS_(2) in 1T-phase reveals the presence of a hidden quantum state, a Mott-insulating phase, and a quantum spin liquid state. The observed phenomenon in these quantum systems makes them a promising candidate for advanced technologies such as quantum computing and communication.

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Vivek Kumar. 2025-07-23. Phonon Dynamics of Topological Quantum Materials. https://arxiv.org/abs/2507.17203

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