Entanglement of two-qubit photon beam by magnetic field

TL;DR

This paper explores how an external magnetic field, mediated through electrons, can influence the entanglement of a two-photon system with different frequencies and polarizations, providing an exact theoretical framework.

Contribution

It introduces a novel theoretical approach to analyze magnetic field effects on photon entanglement via exact solutions involving electron-photon interactions.

Findings

Entanglement measure varies with magnetic field strength.

Exact solutions enable precise calculation of entanglement changes.

Magnetic field can modulate photon entanglement in the system.

Abstract

We have studied the possibility of affecting the entanglement measure of 2-qubit system consisting of two photons with different fixed frequencies but with two arbitrary linear polarizations, moving in the same direction, by the help of an applied external magnetic field. The interaction between the magnetic field and the photons in our model is achieved through intermediate electrons that interact with both the photons and the magnetic field. The possibility of exact theoretical analysis of this scheme is based on known exact solutions that describe the interaction of an electron subjected to an external magnetic field (or a medium of electrons not interacting with each other) with a quantized field of two photons. We adapt these exact solutions to the case under consideration. Using explicit wave functions for the resulting electromagnetic field, we calculate the entanglement measure of the photon beam as a function of the applied magnetic field and parameters of the electron medium.