Quantum plasmonics of finite-size particles with coherent anti-Stokes Raman scattering

• Main Authors: Kam, Chan Hin, Ooi, Raymond Chong Heng
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2019
• Subjects: Nonlinear Optics; Plasmonics; DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/87806; http://hdl.handle.net/10220/49303
• Institution: Nanyang Technological University

We have developed a semianalytical theory to study a quantum plasmonic system composed of a quantum particle and a metallic particle with finite size. The quantum particle is composed of molecules driven by three laser fields and produces a coherent anti-Stokes Raman scattering (CARS) signal which is enhanced by plasmonic resonance of the metallic particle. The enhanced CARS field and the control laser form a Λ scheme that gives highly nonlinear and spatially nonlocal effects. We obtain absorption spectra that show periodic oscillations with radius of the spherical quantum particle, the whispering gallery effect. Plasmonic resonance gives very large and narrow absorption peaks as well as vanishing absorption or Fano dip at specific values of frequency and interparticle distance. The space between the two particles provides a resonant cavity effect which explains the oscillations of absorption power spectra with interparticle distance.