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arXiv · 2210.02639

Optomechanical Effects in Nanocavity-enhanced Resonant Raman Scattering of a Single Molecule

Abstract

In this article, we address the optomechanical effects in surface-enhanced resonant Raman scattering (SERRS) from a single molecule in a nano-particle on mirror (NPoM) nanocavity by developing a quantum master equation theory, which combines macroscopic quantum electrodynamics and electron-vibration interaction within the framework of open quantum system theory. We supplement the theory with electromagnetic simulations and time-dependent density functional theory calculations in order to study the SERRS of a methylene blue molecule in a realistic NPoM nanocavity. The simulations allow us not only to identify the conditions to achieve conventional optomechanical effects, such as vibrational pumping, non-linear scaling of Stokes and anti-Stokes scattering, but also to discovery distinct behaviors, such as the saturation of exciton population, the emergence of Mollow triplet side-bands, and higher-order Raman scattering. All in all, our study might guide further investigations of optomechanical effects in resonant Raman scattering.

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Xuan-Ming Shen, Yuan Zhang, Shunping Zhang, Yao Zhang, Qiu-Shi Meng, Guangchao Zheng, Siyuan Lv, Luxia Wang, Roberto A. Boto, Chongxin Shan, Javier Aizpurua. 2022-10-06. Optomechanical Effects in Nanocavity-enhanced Resonant Raman Scattering of a Single Molecule. https://doi.org/10.1103/physrevb.107.075435

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