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arXiv · 2503.05389

Raman Forbidden Layer-Breathing Modes in Layered Semiconductor Materials Activated by Phonon and Optical Cavity Effects

Miao-Ling Lin·Jiang-Bin Wu·Xue-Lu Liu·Tao Liu·Rui Mei·Heng Wu·Shan Guan·Jia-Liang Xie·Jun-Wei Luo·Lin-Wang Wang·Andrea C. Ferrari·Ping-Heng Tan
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Abstract

We report Raman forbidden layer-breathing modes (LBMs) in layered semiconductor materials (LSMs). The intensity distribution of all observed LBMs depends on layer number, incident light wavelength and refractive index mismatch between LSM and underlying substrate. These results are understood by a Raman scattering theory via the proposed spatial interference model, where the naturally occurring optical and phonon cavities in LSMs enable spatially coherent photon-phonon coupling mediated by the corresponding one-dimensional periodic electronic states. Our work reveals the spatial coherence of photon and phonon fields on the phonon excitation via photon/phonon cavity engineering.

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Miao-Ling Lin, Jiang-Bin Wu, Xue-Lu Liu, Tao Liu, Rui Mei, Heng Wu, Shan Guan, Jia-Liang Xie, Jun-Wei Luo, Lin-Wang Wang, Andrea C. Ferrari, Ping-Heng Tan. 2025-03-07. Raman Forbidden Layer-Breathing Modes in Layered Semiconductor Materials Activated by Phonon and Optical Cavity Effects. https://doi.org/10.1103/physrevlett.134.096903

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