Cavity-Enhanced Two-Photon Interference using Remote Quantum Dot Sources

TL;DR

This paper demonstrates that cavity quantum electrodynamics can significantly enhance quantum interference between remote quantum dot sources, enabling better photon indistinguishability for quantum computing applications.

Contribution

It provides the first experimental investigation of quantum interference between remote quantum dot sources using cavity enhancement, showing improved photon indistinguishability.

Findings

Cavity QED improves interference contrast between remote sources.

Poorly indistinguishable photons can interfere effectively with high-quality photons.

Cavity enhancement facilitates interconnecting multiple quantum devices.

Abstract

Quantum dots in cavities have been shown to be very bright sources of indistinguishable single photons. Yet the quantum interference between two bright quantum dot sources, a critical step for photon based quantum computation, has never been investigated. Here we report on such a measurement, taking advantage of a deterministic fabrication of the devices. We show that cavity quantum electrodynamics can efficiently improve the quantum interference between remote quantum dot sources: poorly indistinguishable photons can still interfere with good contrast with high quality photons emitted by a source in the strong Purcell regime. Our measurements and calculations show that cavity quantum electrodynamics is a powerful tool for interconnecting several devices.