Complete and deterministic analysis for spatial-polarization hyperentangled Greenberger-Horne-Zeilinger states with quantum-dot cavity systems

摘要

Entangled state analysis is one of the basic techniques in quantum information processing. However, it is impossible to fully distinguish the three-photon Greenberger-Horne-Zeilinger (GHZ) states with only linear optical elements. Here, we propose a deterministic scheme to complete three-photon spatial-polarization hyperentangled GHZ-state analysis (HGSA) by using the giant optical Faraday rotation induced by an excess electron spin in a quantum dot inside a one-sided optical microcavity as a result of cavity quantum electrodynamics. It is divided into two steps. The first step is used to distinguish the eight three-photon GHZ states in the spatial-mode degree of freedom (DOF) without destroying the polarization states. The second step is used to distinguish the eight GHZ states in the polarization DOF. This scheme can be generalized to N-photon spatial-polarization HGSA and has useful applications in quantum communication protocols.