A manufacturable platform for photonic quantum computing

TL;DR

This paper presents a scalable, manufacturable silicon photonics platform for quantum computing, demonstrating high-fidelity qubit operations, inter-chip communication, and promising next-generation components.

Contribution

Introduction of a manufacturable silicon photonics platform for quantum computing with integrated modules and high-fidelity operations, enabling scalable photonic quantum systems.

Findings

99.98% state preparation and measurement fidelity

99.50% Hong-Ou-Mandel interference visibility

99.22% two-qubit fusion fidelity

Abstract

Whilst holding great promise for low noise, ease of operation and networking, useful photonic quantum computing has been precluded by the need for beyond-state-of-the-art components, manufactured by the millions. Here we introduce a manufacturable platform for quantum computing with photons. We benchmark a set of monolithically-integrated silicon photonics-based modules to generate, manipulate, network, and detect photonic qubits, demonstrating dual-rail photonic qubits with $99.98\% \pm 0.01\%$ state preparation and measurement fidelity, Hong-Ou-Mandel quantum interference between independent photon sources with $99.50\%\pm0.25\%$ visibility, two-qubit fusion with $99.22\%\pm0.12\%$ fidelity, and a chip-to-chip qubit interconnect with $99.72\%\pm0.04\%$ fidelity, not accounting for loss. In addition, we preview a selection of next generation technologies, demonstrating low-loss silicon nitride waveguides and components, fabrication-tolerant photon sources, high-efficiency photon-number-resolving detectors, low-loss chip-to-fiber coupling, and barium titanate electro-optic phase shifters.