Four-wave mixing signal enhancement and optical bistability of a hybrid metal nanoparticle-quantum dot molecule in a nanomechanical resonator

Abstract

We investigate theoretically four-wave mixing (FWM) response and optical bistability (OB) in a hybrid nanosystem composed of a metal nanoparticle (MNP) and a semiconductor quantum dot (SQD) coupled to a nanomechanical resonator (NR). It is shown that the FWM signal is enhanced by more than three orders of magnitude as compared to that of the system without exciton-phonon interaction, and the FWM signal can also be suppressed significantly and broadened due to the exciton-plasmon interaction. As the MNP couples strongly with the SQD, the bistable FWM response can be achieved by adjusting the SQD-MNP distance and the pumping intensity. For a given pumping constant and a fixed SQD-MNP distance, the enhanced exciton-phonon interaction can promote the occurrence of bistability. Our findings not only present a feasible way to detect the spacing between two nanoparticles, but also hold promise for developing quantum switches and nanoscale rulers.

Tunable Optical Bistability and Tristability in Nonlinear Graphene-Wrapped Nanospheres

“…Correspondingly, the enhancement of local electromagnetic fields shall boost the nonlinear optical effects of the metal/dielectric planar or two- (or three-) dimensional composite microstructures. In addition, hybrid , or two-level systems, which support exciton–phonon/plasmon interaction or systematic self-action, can also result in enhanced nonlinearity and even optical bistability. As one remarkable feature of nonlinearity, optical bistability provides a new way for light to be manipulated by light, where a nonlinear optical system exhibits two distinguished stable excited states for a single input intensity .…”

Projected equations of motion approach to hybrid quantum/classical dynamics in dielectric-metal composites

“…On the other hand, an accurate FDTD model is less crucial if the SQD and MNP are sufficiently far apart. Moreover, the simpler dipolar coupling used in this work is still popular 45,47,48 and the PEOM formalism provides a necessary improvement as attention turns towards ultrafast phenomena.…”

Unidirectional reflectionless light propagation at exceptional points

“…SPPs, which are surface waves propagating along the interface between a metal and a dielectric [49], can concentrate electromagnetic energy at volumes of subwavelength scale and enable the manipulation of light beyond the diffraction limit [50][51][52][53][54][55][56][57][58][59]. Yang and Mei introduced a periodic PT-symmetric modulation on the effective refractive index of a metal-dielectric waveguide in the cylindrical coordinate system.…”