Implementation Of Entanglement State Analyzsis Using Quantum Dot Spins And Double Sided Optical Microcavity Coupled System

In recent years, quantum information science based on quantum mechanics get rapid development and improvement. It can be used to solve many questions about computation that can not be achieved with classical physics. Quantum entangle-ment is a peculiar physical phenomenon of quantum mechanics. It is an important resource in quantum information science and has been widely studied. Quantum entanglement analyzer can effectively distinguish entanglement state, it is of great meaningful to realize quantum communication and computation. Especially the two-particle or multi-particle entanglement state analyzer without destroying the entanglement state can save quantum resources in a certain extent and make quan-tum information process more efficient. Therefore, the research of complete and nondestructive entanglement state analyzer plays a vital role in quantum informa-tion processing. In this paper, we first propose a electron-photon controlled phase gate with the interaction of photon and electron spin inside quantum-dot system in a optical double-sided microcavity. And then we build a Bell state analyzer, GHZ state analyzer and N-particle GHZ state analyzer in weak coupling regimes, respec-tively. The outstanding feature of our schemes are not only nondestructive but also have high efficiency and high fidelity. Furthermore, compared with other entangle-mengt state analyzers, our scheme can save a great number of photons. Because of our scheme works in weak coupling regimes, it greatly reduces the experimental requirements and it is feasible with current technology. It is very important for quantum information processing.