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Probing anharmonic phonons in WS₂ van der Waals crystal by Raman spectroscopy and machine learning.

ABSTRACT: Understanding the optothermal physics of quantum materials will enable the efficient design of next-generation photonic and superconducting circuits. Anharmonic phonon dynamics is central to strongly interacting optothermal physics. This is because the pressure of a gas of anharmonic phonons is temperature dependent. Phonon-phonon and electron-phonon quantum interactions contribute to the anharmonic phonon effect. Here we have studied the optothermal properties of physically exfoliated WS₂ van der Waals crystal via temperature-dependent Raman spectroscopy and machine learning strategies. This fundamental investigation will lead to unveiling the dependence of temperature on in-plane and out-of-plane Raman shifts (Raman thermometry) of WS₂ to study the thermal conductivity, hot carrier diffusion coefficient, and thermal expansion coefficient.

SUBMITTER: Okeke C

PROVIDER: S-EPMC10362287 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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Probing anharmonic phonons in WS2 van der Waals crystal by Raman spectroscopy and machine learning.

Okeke Chisom C Juma Isaac I Cobarrubia Antonio A Schottle Nicholas N Maddah Hisham H Mortazavi Mansour M Behura Sanjay K SK

iScience 20230618 7

Understanding the optothermal physics of quantum materials will enable the efficient design of next-generation photonic and superconducting circuits. Anharmonic phonon dynamics is central to strongly interacting optothermal physics. This is because the pressure of a gas of anharmonic phonons is temperature dependent. Phonon-phonon and electron-phonon quantum interactions contribute to the anharmonic phonon effect. Here we have studied the optothermal properties of physically exfoliated WS2< ...[more]

PMID: 37485362

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