Polarization-path-frequency entanglement using interferometry and frequency shifters

TL;DR

This paper presents a scheme to generate and control hyperentangled photon states across polarization, path, and frequency degrees of freedom using interferometry and frequency shifters, advancing quantum information processing.

Contribution

It introduces a novel method to produce and manipulate polarization-path-frequency entanglement via an interferometric setup with controllable dynamics.

Findings

Demonstrated control of entanglement between subspaces using negativity measures

Proposed a practical approach for generating hyperentangled states

Progress towards experimental realization of quantum walks with light

Abstract

Higher dimensional Hilbert space along with ability to control multiple degrees of freedom of photon and entangle them has enabled new quantum protocols for various quantum information processing applications. Here, we propose a scheme to generate and control polarization-path frequency entanglement using the operative elements required to implement a polarization-controlled quantum walk in the path(position) space and frequency domain. Hyperentangled states manifests in the controlled dynamics using an interferometric setup where half-wave plates, beam-splitters and frequency shifters such as those based on the electro-optic effect are used to manipulate the polarization, path and frequency degrees of freedom respectively. The emphasis is on utilizing the polarization to influence the movement to a specific value in the frequency and position space. Negativity between the subspaces is calculated to demonstrate the controllability of the entanglement between them. Progress reported with experimental demonstration of realization of quantum walk using quantum states of light makes quantum walks a practical approach to generate hyperentangled states.