# Detector-Independent Verification of Quantum Light

## TL;DR

This paper presents a detector-independent method for verifying nonclassical light using multiplexing, allowing for the detection of quantum properties without detailed detector calibration, demonstrated with superconducting sensors.

## Contribution

It introduces a multiplexing-based verification technique that is independent of detector specifics, enabling reliable nonclassical light verification without detector characterization.

## Key findings

- Successfully verified nonclassicality of multiphoton states
- Demonstrated detector-independent verification with superconducting sensors
- Established bounds distinguishing classical from quantum light

## Abstract

We introduce a method for the verification of nonclassical light which is independent of the complex interaction between the generated light and the material of the detectors. This is accomplished by means of a multiplexing arrangement. Its theoretical description yields that the coincidence statistics of this measurement layout is a mixture of multinomial distributions for any classical light field and any type of detector. This allows us to formulate bounds on the statistical properties of classical states. We apply our directly accessible method to heralded multiphoton states which are detected with a single multiplexing step only and two detectors, which are in our work superconducting transition-edge sensors. The nonclassicality of the generated light is verified and characterized through the violation of the classical bounds without the need for characterizing the used detectors.