Heralded quantum repeater for a quantum communication network based on quantum dots embedded in optical microcavities

TL;DR

This paper introduces a heralded quantum repeater protocol using quantum dots in microcavities, enabling efficient entanglement distribution and purification for quantum communication networks with current technology.

Contribution

It presents a novel protocol leveraging time-bin encoding and a single-photon parity-check detector to improve entanglement distribution and purification efficiency in quantum repeaters.

Findings

Deterministic entanglement distribution with one fiber per photon

Enhanced entanglement purification efficiency

Feasibility with current quantum dot and microcavity technology

Abstract

We propose a heralded quantum repeater protocol based on the general interface between the circularly polarized photon and the quantum dot embedded in a double-sided optical microcavity. Our effective time-bin encoding on photons results in the deterministic faithful entanglement distribution with one optical fiber for the transmission of each photon in our protocol, not two or more. Our efficient parity-check detector implemented with only one input-output process of a single photon as a result of cavity quantum electrodynamics makes the entanglement channel extension and entanglement purification in quantum repeater far more efficient than others, and it has the potential application in fault-tolerant quantum computation as well. Meanwhile, the deviation from a collective-noise channel leads to some phase-flip errors on the nonlocal electron spins shared by the parties and these errors can be depressed by our simplified entanglement purification process. Finally, we discuss the performance of our proposal, concluding that it is feasible with current technology.