Optical Entanglement of Distinguishable Quantum Emitters

TL;DR

This paper introduces a method to entangle solid-state quantum emitters with significantly different optical transition frequencies using electro-optic modulation, advancing scalable quantum networks.

Contribution

The authors demonstrate a protocol that entangles distinguishable quantum emitters separated by many linewidths, enabling scalable quantum information processing.

Findings

Successfully entangled two silicon-vacancy centers separated by 7.4 GHz.

Enabled individual addressing and readout of each emitter.

Demonstrated parallel control and entanglement of multiple emitters.

Abstract

Solid-state quantum emitters are promising candidates for the realization of quantum networks, owing to their long-lived spin memories, high-fidelity local operations, and optical connectivity for long-range entanglement. However, due to differences in local environment, solid-state emitters typically feature a range of distinct transition frequencies, which makes it challenging to create optically mediated entanglement between arbitrary emitter pairs. We propose and demonstrate an efficient method for entangling emitters with optical transitions separated by many linewidths. In our approach, electro-optic modulators enable a single photon to herald a parity measurement on a pair of spin qubits. We experimentally demonstrate the protocol using two silicon-vacancy center sin a diamond nanophotonic cavity, with optical transitions separated by 7.4 GHz. Working with distinguishable emitters allows for individual qubit addressing and readout, enabling parallel control and entanglement of both co-located and spatially separated emitters, a key step towards scaling up quantum information processing systems