What does it take to see entanglement?

TL;DR

This paper proposes a novel method to detect quantum entanglement directly with the human eye, eliminating electronic detectors, by using phase space displacement to visualize micro entanglement.

Contribution

It introduces a new approach to observe entanglement visually, bypassing traditional electronic detection methods, and demonstrates its feasibility through a theoretical study.

Findings

Entanglement can be detected visually using phase space displacement.

The proposed method eliminates the need for electronic detectors in entanglement observation.

Feasibility analysis supports the potential for eye-based entanglement detection.

Abstract

Tremendous progress has been realized in quantum optics for engineering and detecting the quantum properties of light. Today, photon pairs are routinely created in entangled states. Entanglement is revealed using single-photon detectors in which a single photon triggers an avalanche current. The resulting signal is then processed and stored in a computer. Here, we propose an approach to get rid of all the electronic devices between the photons and the experimentalist i.e. to use the experimentalist's eye to detect entanglement. We show in particular, that the micro entanglement that is produced by sending a single photon into a beam-splitter can be detected with the eye using the magnifying glass of a displacement in phase space. The feasibility study convincingly demonstrates the possibility to realize the first experiment where entanglement is observed with the eye.