基于腔QED制备四粒子super singlets.

A scheme for preparation of 4 - qubit supersinglets in microwave cavity quantum electrodynamics (QED) based on the resonant atom - cavity interaction via two - photon process is proposed. Initially, cavities are only prepared in the vacuum states and a three - level S - style Rydberg atom is prepared in the excited state, and then, the atom is sequentially sent through four cavities . After an appropriate atom - cavity interaction process and measurement on the atomic state, these cavities will be projected onto the supersinglets with maximum fidelity. The influence of atom - cavity coupling constant on fidelity as well as the practical feasibility of the scheme are discussed. Numerical calculation demonstrates that the fidelity is more sensitive to the interaction time for a larger coupling constant when the detuning equals to zero, and the fidelity of the entangled state varies with the interaction time. [ABSTRACT FROM AUTHOR]