Sub-Poissonian photon statistics in quantum dot-metal nanoparticles hybrid system with gain media

In this paper, we theoretically demonstrate the sub-Poissonian photon statistics in gain-assisted quantum dot-metal nanoparticles (QD-MNPs) hybrid system with nanoscale footprint. The gain media is introduced to reduce the dissipation of localized surface plasmons and consequently the quality factor of MNPs is improved by adjusting the gain coefficient. Simulated by finite element method (FEM), the Fano resonance is observed in the absorption cross section spectrum of the hybrid system. Considering MNPs and gain media together as a single mode cavity, the system is investigated within the framework of cavity quantum electrodynamics by fitting necessary parameters with FEM. The numerical results show that the coupling between QD and MNPs falls in strong coupling regime and zero delay second-order autocorrelation function g(2)(0) = 0.356 can be achieved with proper choice of gain coefficient. Moreover, the sub-Poissonian photon statistics can be maintained in a large variation range of gain coefficient and a certain degree of detuning between QD and cavity is allowed.