Wigner distribution function and entanglement of generalized quantum optical vortex

TL;DR

This paper calculates the Wigner distribution of quantum optical elliptical vortices generated by coupled squeezed states, revealing how entanglement varies with vorticity and squeezing parameters, relevant for quantum information processing.

Contribution

It introduces a method to analyze entanglement in quantum optical vortices using Wigner functions, highlighting a counterintuitive relationship between vorticity and entanglement.

Findings

Entanglement decreases with higher vorticity beyond a critical squeezing.

Coupling methods include beam splitter and dual channel directional coupler.

Wigner function analysis reveals non-classical features of the vortex states.

Abstract

We calculate the Wigner (quasi)probability distribution function of the quantum optical elliptical vortex (QEV), generated by coupling squeezed vacuum states of two modes. The coupling between the two modes is performed by using beam splitter (BS) or a dual channel directional coupler (DCDC). The quantum interference due to the coupling between the two modes promises the generation of controlled entanglement for quantum computation and quantum tomography. We compute the entanglement of such QEV formed by non-classical radiation field, using Wigner function. We report a critical squeezing parameter above which the entanglement is less for higher vorticity, which is counter intuitive.