Photonic Counterparts of Cooper Pairs

TL;DR

This paper demonstrates that photons can form Cooper-like pairs through virtual vibrational exchanges in media, leading to enhanced pair correlations, supported by experimental Raman measurements.

Contribution

It introduces the concept of photonic Cooper pairs mediated by virtual vibrations, extending superconductivity principles to photon interactions in transparent media.

Findings

Photon pairs exchange virtual vibrations similar to electron Cooper pairs.

Enhanced photon pair correlations observed away from Raman resonances.

Experimental data confirms theoretical predictions without fitting parameters.

Abstract

The microscopic theory of superconductivity raised the disruptive idea that electrons couple through the elusive exchange of virtual phonons, overcoming the strong Coulomb repulsion to form Cooper pairs. Light is also known to interact with atomic vibrations, as for example in the Raman effect. We show that photon pairs exchange virtual vibrations in transparent media, leading to an effective photon-photon interaction identical to that for electrons in BCS theory of supercondutivity, in spite of the fact that photons are bosons. In this scenario, photons may exchange energy without matching a quantum of vibration of the medium. As a result, pair correlations for photons scattered away from the Raman resonances are expected to be enhanced. Experimental demonstration of this effect is provided here by time correlated Raman measurements in different media. The experimental data confirm our theoretical interpretation of a photonic Cooper pairing, without the need for any fitting parameters.