Higher-dimensional symmetric informationally complete measurement via programmable photonic integrated optics

TL;DR

This paper demonstrates a programmable integrated photonic device capable of implementing high-fidelity symmetric informationally complete measurements on three-level quantum systems, advancing quantum measurement technology.

Contribution

It introduces a scalable, high-fidelity, programmable photonic platform for realizing complex higher-dimensional quantum measurements.

Findings

Achieved high-fidelity SIC measurements on qutrits

Performed near-optimal quantum state discrimination

Surpassed projective measurement limits in quantum random number generation

Abstract

Symmetric informationally complete measurements are both important building blocks in many quantum information protocols and the seminal example of a generalised, non-orthogonal, quantum measurement. In higher-dimensional systems, these measurements become both increasingly interesting and increasingly complex to implement. Here, we demonstrate an integrated quantum photonic platform to realize such a measurement on three-level quantum systems. The device operates at the high fidelities necessary for verifying a genuine many-outcome quantum measurement, performing near-optimal quantum state discrimination, and beating the projective limit in quantum random number generation. Moreover, it is programmable and can readily implement other quantum measurements at similarly high quality. Our work paves the way for the implementation of sophisticated higher-dimensional quantum measurements that go beyond the traditional orthogonal projections.