Generation and complete nondestructive analysis of hyperentanglement assisted by nitrogen-vacancy centers in resonators

摘要

We present two efficient schemes for the deterministic generation and thecomplete nondestructive analysis of hyperentangled Bell states in both thepolarization and spatial-mode degrees of freedom (DOFs) of two-photon systems,assisted by the nitrogen-vacancy (NV) centers in diamonds coupled tomicrotoroidal resonators as a result of cavity quantum electrodynamics (QED).With the input-output process of photons, two-photon polarization-spatialhyperentangled Bell states can be generated in a deterministic way and theircomplete nondestructive analysis can be achieved. These schemes can begeneralized to generate and analyze hyperentangled Greenberger-Horne-Zeilingerstates of multi-photon systems as well. Compared with previous works, these twoschemes relax the difficulty of their implementation in experiment as it is notdifficult to obtain the $\pi$ phase shift in single-sided NV-cavity systems.Moreover, our schemes do not require that the transmission for the uncoupledcavity is balanceable with the reflectance for the coupled cavity. Ourcalculations show that these schemes can reach a high fidelity and efficiencywith current technology, which may be a benefit to long-distance high-capacityquantum communication with two DOFs of photon systems.