Boson Sampling on a Photonic Chip

TL;DR

This paper demonstrates a photonic quantum boson sampling device that leverages nonclassical photon interference in an integrated circuit, providing a promising step towards quantum advantage in specialized computational tasks.

Contribution

The authors built and benchmarked a quantum boson sampling machine using integrated photonics with three and four photons, advancing experimental quantum photonics.

Findings

Successfully sampled photon distributions with 3 and 4 photons

Analyzed sources of sampling inaccuracy in the device

Paved the way for larger, more complex quantum photonic devices

Abstract

While universal quantum computers ideally solve problems such as factoring integers exponentially more efficiently than classical machines, the formidable challenges in building such devices motivate the demonstration of simpler, problem-specific algorithms that still promise a quantum speedup. We construct a quantum boson sampling machine (QBSM) to sample the output distribution resulting from the nonclassical interference of photons in an integrated photonic circuit, a problem thought to be exponentially hard to solve classically. Unlike universal quantum computation, boson sampling merely requires indistinguishable photons, linear state evolution, and detectors. We benchmark our QBSM with three and four photons and analyze sources of sampling inaccuracy. Our studies pave the way to larger devices that could offer the first definitive quantum-enhanced computation.