Violating Bell inequality using weak coherent states

TL;DR

This paper experimentally demonstrates the violation of Bell inequalities using phase-randomized weak coherent states from a continuous-wave laser, highlighting the quantum nature of classical-like sources.

Contribution

It is the first to show Bell inequality violation with phase-randomized weak coherent states from a continuous laser source.

Findings

Successful violation of CHSH inequality with weak coherent states

Quantum nature can be revealed from classical sources using this method

Experimental setup using continuous-wave laser and phase randomization

Abstract

We present an experimental investigation of two-photon interference using a continuous-wave laser. We demonstrate the violation of the CHSH inequality using the phase randomized weak coherent states from a continuous wave laser. Our implementation serves as an approach to reveal the quantum nature of a source that is considered to be a classical source.