Complete hyperentangled-Bell-state analysis for photon systems assisted by quantum-dot spins in optical microcavities

TL;DR

This paper presents a scheme to fully distinguish 16 hyperentangled Bell states across polarization and spatial modes using quantum dot-cavity systems, enhancing quantum communication capabilities.

Contribution

It introduces a novel method employing quantum-dot microcavities for complete hyperentangled Bell-state analysis, surpassing previous linear optical limitations.

Findings

Achieves complete discrimination of 16 hyperentangled Bell states.

Demonstrates application in hyperentanglement swapping.

Potential to increase quantum communication channel capacity.

Abstract

Bell-state analysis (BSA) is essential in quantum communication, but it is impossible to distinguish unambiguously the four Bell states in the polarization degree of freedom (DOF) of two-photon systems with only linear optical elements, except for the case in which the BSA is assisted with hyperentangled states, the simultaneous entanglement in more than one DOF. Here, we propose a scheme to distinguish completely the 16 hyperentangled Bell states in both the polarization and the spatial-mode DOFs of two-photon systems, by using the giant nonlinear optics in quantum dot-cavity systems. This scheme can be applied to increase the channel capacity of long-distance quantum communication based on hyperentanglement, such as entanglement swapping, teleportation, and superdense coding. We use hyperentanglement swapping as an example to show the application of this HBSA.