Strong coupling among semiconductor quantum dots induced by a metal nanoparticle
Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics, Shanghai Jiao Tong University, 800 DongChuan Road, Shanghai 200240, China
Nanoscale Research Letters 2012, 7:95 doi:10.1186/1556-276X-7-95Published: 1 February 2012
Based on cavity quantum electrodynamics (QED), we investigate the light-matter interaction between surface plasmon polaritons (SPP) in a metal nanoparticle (MNP) and the excitons in semiconductor quantum dots (SQDs) in an SQD-MNP coupled system. We propose a quantum transformation method to strongly reveal the exciton energy shift and the modified decay rate of SQD as well as the coupling among SQDs. To obtain these parameters, a simple system composed of an SQD, an MNP, and a weak signal light is designed. Furthermore, we consider a model to demonstrate the coupling of two SQDs mediated by SPP field under two cases. It is shown that two SQDs can be entangled in the presence of MNP. A high concurrence can be achieved, which is the best evidence that the coupling among SQDs induced by SPP field in MNP. This scheme may have the potential applications in all-optical plasmon-enhanced nanoscale devices.