Resumen de Light switch based on a nanoparticle chain and on the optomechanically generated field enhancement
Alicia Fresno Hernández, Manuel Ignacio Marqués Ponce, Carmen Vázquez
This paper presents an investigation into the resonant cumulative field enhancement that plasmonic nanoparticle chains experience in a light field, and how this enhancement is affected by the chain's orientation with respect to the field. We derive analytical expressions for the optical torque and equilibrium configuration of the chain, and demonstrate how stable orientations are triggered by geometric resonance conditions. We also validate our analytical predictions using numerical calculations based on the coupled dipoles method, specifically for a chain of silver nanoparticles. Furthermore, we demonstrate that this resonance-driven optical torque can be used to tune the orientation of the chain based on the wavelength of the incident radiation. The changes in the orientation, depending on wavelength, lead to reflected light which can be focused onto the different cores of a fiber, making this device suitable as a wavelength selective switch.
