Complete deterministic multi-electron Greenberger-Horne-Zeilinger state analyzer for quantum communication

TL;DR

This paper introduces a complete scheme for analyzing multi-electron GHZ states using photon-electron interactions in quantum dots, enabling full discrimination while preserving initial states for future tasks, with applications in quantum repeaters.

Contribution

It presents a novel, complete GHZ-state analyzer for multi-electron spins that preserves initial states and facilitates quantum communication.

Findings

All multi-spin GHZ states can be fully discriminated.

Initial entangled states remain after analysis.

Suitable for quantum repeater applications.

Abstract

We present a scheme for the multi-electron Greenberger-Horne-Zeilinger (GHZ) state analyzer, resorting to an interface between the polarization of a probe photon and the spin of an electron in a quantum dot embedded in a microcavity. All the multi-spin GHZ states can be completely discriminated by using single-photon detectors and linear optical elements. Our scheme has some features. First, it is a complete GHZ-state analyzer for multi-electron spin systems. Second, the initial entangled states remain after being identified and they can be used for a successive task. Third, the electron qubits are static and the photons play a role of a medium for information transfer, which has a good application in quantum repeater in which the electron qubits are used to store the information and the photon qubits are used to transfer the information between others.