Analysis of photon-mediated entanglement between distinguishable matter qubits

TL;DR

This paper theoretically investigates how to establish high-fidelity entanglement between distinguishable matter qubits via photon interference, analyzing mode-matching requirements and demonstrating feasibility with current technology.

Contribution

It provides a general framework for assessing entanglement fidelity limits based on photon mode mismatches and applies this to various quantum memory systems.

Findings

High entanglement fidelities (>99%) are achievable with current techniques.

Mode-matching requirements are critical for maintaining fidelity.

Feasible entanglement rates for quantum networks are demonstrated.

Abstract

We theoretically evaluate establishing remote entanglement between distinguishable matter qubits through interference and detection of two emitted photons. The fidelity of the entanglement operation is analyzed as a function of the temporal and frequency mode-matching between the photons emitted from each quantum memory. With a general analysis, we define limits on the absolute magnitudes of temporal and frequency mode-mismatches in order to maintain entanglement fidelities greater than 99% with two-photon detection efficiencies greater than 90%. We apply our analysis to several selected systems of quantum memories. Results indicate that high fidelities may be achieved in each system using current experimental techniques, while maintaining acceptable rates of entanglement. Thus, it might be possible to use two-photon-mediated entanglement operations between distinguishable quantum memories to establish a network for quantum communication and distributed quantum computation.