Identification of vibrational mode symmetry and phonon anharmonicity in SbCrSe3 single crystal using Raman spectroscopy
Résumé
Developing an understanding of the physics underlying vibrational phonon modes, which are strongly related to thermal transport, has attracted significant research interest. Herein, we report the successful synthesis of bulk SbCrSe3 single crystal and its thermal transport property over the temperature range from 2 to 300 K. Using angle-resolved polarized Raman spectroscopy (ARPRS) and group theory calculation, the vibrational symmetry of each observed Raman mode in the cleaved (00l) crystal plane of SbCrSe3 is identified for the first time, and then further verified through first-principles calculations. The ARPRS results of some Raman modes (e.g., A2g ∼4 cm−1 and A 7g ∼185 cm−1) can be adopted to determine the crystalline orientation. More importantly, the temperature dependence of the lattice thermal conductivity (κL) is revealed to be more accurately depicted by the three-phonon scattering processes throughout the measured temperature range, substantiated by in-situ Raman spectroscopy analysis and the model-predicted κL. These results reveal the fundamental physics of thermal transport for SbCrSe3 from a completely new perspective and should thus ignite research interest in the thermal properties of other low-dimensional materials using the same strategy.
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