Visibility-based hypothesis testing using higher-order optical interference

TL;DR

This paper introduces a robust method for hypothesis testing using higher-order optical interference that works without a shared phase reference, enabling efficient quantum data comparison even in low-photon conditions.

Contribution

It presents an experimental demonstration of visibility hypothesis discrimination based on higher-order interference, expanding quantum protocol robustness without phase locking.

Findings

Effective binary discrimination of visibility hypotheses achieved

Protocol operates efficiently in the few-photon regime

Robustness against phase randomness demonstrated

Abstract

Many quantum information protocols rely on optical interference to compare datasets with efficiency or security unattainable by classical means. Standard implementations exploit first-order coherence between signals whose preparation requires a shared phase reference. Here, we analyze and experimentally demonstrate binary discrimination of visibility hypotheses based on higher-order interference for optical signals with a random relative phase. This provides a robust protocol implementation primitive when a phase lock is unavailable or impractical. With the primitive cost quantified by the total detected optical energy, optimal operation is typically reached in the few-photon regime.