Waveguide photon-number-resolving detectors for quantum photonic integrated circuits

TL;DR

This paper introduces waveguide photon-number-resolving detectors integrated on GaAs/AlGaAs waveguides, capable of detecting up to four photons with a single read-out, advancing scalable quantum photonic circuits.

Contribution

It demonstrates a novel waveguide photon-number-resolving detector with four-photon detection capability on a monolithic integrated platform.

Findings

Detected 0-4 photons with a four-wire WPNRD

Achieved ~24% quantum efficiency at 1310 nm

Operates with a single electrical read-out

Abstract

Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been recently shown to be compatible with single-photon sources for a monolithic integration. While standard WSPDs offer single-photon sensitivity, more complex superconducting nanowire structures can be configured to have photon-number-resolving capability. In this work, we present waveguide photon-number-resolving detectors (WPNRDs) on GaAs/Al0.75Ga0.25As ridge waveguides based on a series connection of nanowires. The detection of 0-4 photons has been demonstrated with a four-wire WPNRD, having a single electrical read-out. A device quantum efficiency ~24 % is reported at 1310 nm for the TE polarization.