Entanglement of two quantum dots with dipole–dipole interaction coupled to a cavity in plasmonic waveguide system

We investigate quantum entanglement between two quantum dots (QDs) with dipole–dipole interaction (DDI) in plasmonic waveguide system where a cavity is coupled to the QDs but decoupled from the waveguide. The real-space Hamiltonian and the concurrence are used in describing the composite quantum system and quantifying the entanglement, respectively. We analyze the influence of DDI on the entanglement and propose several effective schemes to achieve high entanglement by modulating the incident frequency, the resonant frequency of the cavity, the QD-cavity coupling strength and so on. Moreover, we demonstrate that coupling between the QDs and the cavity can enhance the entanglement of two QDs.