Wang Yujing, Ye Han, Yu Zhongyuan, Liu Yumin, Xu Wenbin
State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing, 100876, China.
Science and Technology on Optical Radiation Laboratory, Beijing, 100854, China.
Sci Rep. 2019 Jul 12;9(1):10088. doi: 10.1038/s41598-019-46576-z.
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(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.
在本文中，我们从理论上证明了具有纳米级尺寸的增益辅助量子点-金属纳米颗粒（QD-MNPs）混合系统中的亚泊松光子统计特性。引入增益介质以减少局域表面等离子体的耗散，从而通过调整增益系数提高MNPs的品质因数。通过有限元方法（FEM）模拟，在混合系统的吸收截面光谱中观察到了法诺共振。将MNPs和增益介质一起视为单模腔，通过用FEM拟合必要参数，在腔量子电动力学框架内对该系统进行了研究。数值结果表明，量子点与MNPs之间的耦合处于强耦合区域，通过适当选择增益系数可以实现零延迟二阶自相关函数g(0) = 0.356。此外，在增益系数的较大变化范围内可以保持亚泊松光子统计特性，并且允许量子点与腔之间存在一定程度的失谐。
