Integrated photonic Galton board and its application for photon counting

TL;DR

This paper introduces a photonic Galton board integrated on-chip, capable of single-photon interference observation, photon counting, and photon-number resolution, advancing quantum optics and computing applications.

Contribution

It presents a novel integrated photonic Galton board with photon-number-resolving detectors, enabling scalable quantum optics experiments on-chip.

Findings

Demonstrated on-chip single-photon interference observation

Achieved photon-number-resolving high-speed photon counting

Showed compatibility of detector arrays with photonic circuits

Abstract

The Galton board is a desktop probability machine traditionally used to visualize the principles of statistical physics with classical particles. Here, we demonstrate a photonic Galton board that enables on-chip observation of single-photon interference. The photonic Galton board, which can be considered as a simplified Boson sampler, consists of a directional coupler matrix terminated by an array of superconducting nanowire detectors to provide spatiotemporal resolution. This design also allows for photon-number-resolving capability, making it suitable for high-speed photon counting. Our results demonstrate the compatibility between single-photon detector array and photonic integrated circuits, paving the way for implementing on-chip large-scale quantum optics experiments and photonic quantum computing.