Probing anharmonic phonons in WS2 van der Waals crystal by Raman spectroscopy and machine learning
Chisom Okeke,
Isaac Juma,
Antonio Cobarrubia,
Nicholas Schottle,
Hisham Maddah,
Mansour Mortazavi,
Sanjay K. Behura
Affiliations
Chisom Okeke
Department of Mathematics and Computer Science and Department of Chemistry and Physics, University of Arkansas at Pine Bluff, 1200 N. University Drive, Pine Bluff, AR 71601, United States
Isaac Juma
Department of Mathematics and Computer Science and Department of Chemistry and Physics, University of Arkansas at Pine Bluff, 1200 N. University Drive, Pine Bluff, AR 71601, United States
Antonio Cobarrubia
Department of Physics, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States; Computational Science Research Center, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States
Nicholas Schottle
Department of Physics, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States
Hisham Maddah
Department of Chemical Engineering, King Abdulaziz University, Rabigh 21911, Saudi Arabia
Mansour Mortazavi
Department of Mathematics and Computer Science and Department of Chemistry and Physics, University of Arkansas at Pine Bluff, 1200 N. University Drive, Pine Bluff, AR 71601, United States
Sanjay K. Behura
Department of Physics, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States; Corresponding author
Summary: 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.
