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Raman Tensor of van der Waals MoSe2
Mingge Jin1, Wei Zheng1, Ying Ding1
1State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials, Sun Yat-sen University, Guangzhou 510275, China.
The Journal of Physical Chemistry Letters
|May 13, 2020
Summary
This study investigates the Raman tensor of molybdenum selenide (MoSe2), crucial for understanding its light scattering. Researchers revealed photon-energy-dependent phase differences in MoSe2
Area of Science:
- Materials Science
- Condensed Matter Physics
- Spectroscopy
Background:
- Molybdenum selenide (MoSe2) exhibits anisotropic light absorption and scattering due to its van der Waals layered structure.
- The Raman tensor of MoSe2 is critical for understanding inelastic light scattering anisotropy, but current studies are insufficient.
Purpose of the Study:
- To investigate the out-of-plane anisotropy of molybdenum selenide (MoSe2).
- To experimentally and theoretically abstract complete Raman tensors for MoSe2.
- To elucidate the relationship between optical absorption properties and Raman tensor characteristics.
Main Methods:
- Angle-resolved polarized Raman (APR) spectroscopy was systematically employed.
- First-principles calculations were utilized to determine Raman tensor forms under varying laser excitation conditions.
- Anisotropic optical absorption properties of MoSe2 were studied.
Main Results:
- Complete Raman tensors were abstracted both experimentally and theoretically.
- Different laser excitation conditions result in various Raman tensor forms for MoSe2.
- A specific phase difference between Raman tensor elements of the A1 mode was identified and linked to photon energy.
Conclusions:
- The study successfully characterized the out-of-plane anisotropy of MoSe2.
- Photon-energy-dependent phase differences in the Raman tensor are attributed to the dispersion and absorption properties of MoSe2.
- This work provides a deeper understanding of light-matter interactions in MoSe2.
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