Experimental nonlocality-based randomness generation with non-projective measurements

TL;DR

This paper demonstrates that non-projective measurements on entangled photons can generate more certified randomness than traditional projective measurements, advancing quantum randomness generation technology.

Contribution

It introduces an optical setup using non-projective three-outcome measurements to enhance randomness generation from entangled qubits.

Findings

Achieved over 27% increase in randomness compared to projective measurements.

Generated more than one bit of randomness from a single entangled pair.

Certified randomness through Bell non-local correlations and EPR steering.

Abstract

We report on an optical setup generating more than one bit of randomness from one entangled bit (i.e. a maximally entangled state of two-qubits). The amount of randomness is certified through the observation of Bell non-local correlations. To attain this result we implemented a high-purity entanglement source and a non-projective three-outcome measurement. Our implementation achieves a gain of 27$\%$ of randomness as compared with the standard methods using projective measurements. Additionally we estimate the amount of randomness certified in a one-sided device independent scenario, through the observation of EPR steering. Our results prove that non-projective quantum measurements allows extending the limits for nonlocality-based certified randomness generation using current technology.