Self-assisted deterministic hyperentangled-Bell-state analysis for polarization and double longitudinal momentum degrees of freedom of photon system

Abstract

Hyperentangled state analysis is an important module in high-capacity quantum communication. We present a self-assisted deterministic hyperentangled-Bell-state analysis (HBSA) scheme for photon system entangled in three degrees of freedom (DOFs), where 64 polarization-double longitudinal momentum hyperentangled Bell states are completely distinguished. In this HBSA scheme, the four first longitudinal momentum Bell states are distinguished determinately by nondestructive first longitudinal momentum Bell state analyzer, which is constructed with cross-Kerr nonlinearity medium. The 16 second longitudinal momentum-polarization hyperentangled Bell states are distinguished determinately by self-assisted second longitudinal momentum-polarization hyperentangled Bell state analyzer using linear optical elements, where the first longitudinal momentum Bell state and time-bin entangled state are used as auxiliary. Using this self-assisted method, the application of nonlinear optical resource in HBSA scheme has been largely reduced, which makes this self-assisted deterministic HBSA scheme has potential application prospects in high-capacity quantum communication.

Complete analysis of hyperentangled Bell state in three degrees of freedom using Kerr effect and self-assisted mechanism

“…Therefore, our scheme is easier to realize, and will have a higher efficiency. Compared with the scheme of Yu et al [43], in which the self-assisted mechanism and Kerr effect are also exploited, our scheme does not need the auxiliary entanglement in the fourth DOF. In 2007, Li and Ghose investigated the distinguishability of HBSA with linear optics and auxiliary entanglement, and they found that the auxiliary Bell state in the third DOF cannot accomplish the complete HBSA in two DOFs [26].…”

“…These nonlinear interactions can be used to construct the quantum parity-check gate and the quantum swap gate, both of which are useful for the complete hyperentangled state analysis. However, most of the existing complete HBSA schemes work with photonic hyperentanglement in just two different DOFs, and only a few schemes focus on the complete HBSA for photon system in more than two DOFs [40][41][42][43][44][45]. In 2016, Liu et al presented a nondestructive scheme to completely distinguish the hyperentangled Bell states in three DOFs with the help of cross-Kerr nonlinearity [40].…”