Simulating Bell inequalities violation with classical optics encoded qbits

TL;DR

This paper demonstrates a classical optics setup that simulates quantum entanglement and Bell inequality violations by encoding qubits in electromagnetic waves and using optical processing to measure correlations.

Contribution

It introduces a novel classical optics method to simulate quantum entanglement and Bell inequality violations without quantum systems.

Findings

Bell inequality violations simulated with classical optics

Optical encoding of entangled qubits demonstrated

Correlations exceed local realism bounds

Abstract

We present here a classical optics device based on an imaging architecture as analogy of a quantum system where the violation of the Bell inequality can be evidenced. In our case, the two qbits entangled state needed to obtain non classical correlations is encoded using an electromagnetic wave modulated in amplitude and phase. Computational states are represented in a way where each one of the two qbits is associated with two orthogonal directions in the input plane. In addition, unitary operations involved in the measurement of the observables are simulated with the use of a coherent optical processor. The images obtained in the output of the process, contain all the information about the joint, marginal and conditional probabilities. By measuring the intensity distribution in the image plane we evaluate the mean values of the simulated observables. The obtained experimental results show, in an illustrative manner, how some correlations of Clauser-Horne-Shimony-Holt type exceed the upper bound imposed by the local realism hypothesis as a consequence of the joint effect of entanglement and two-particle interference.