Quantum Walk with a four-dimensional coin

TL;DR

This paper explores the physical realization of a discrete-time quantum walk using a photon with a four-dimensional coin, employing polarization and orbital angular momentum states, and discusses potential experimental outcomes.

Contribution

It introduces a method to implement a four-dimensional quantum coin using photon internal states and details the experimental setup needed.

Findings

Proposed a physical setup for a four-dimensional quantum walk.

Outlined the components required for implementation.

Illustrated potential experimental results.

Abstract

We examine the physical implementation of a discrete time quantum walk with a four-dimensional coin. Our quantum walker is a photon moving repeatedly through a time delay loop, with time being our position space. The quantum coin is implemented using the internal states of the photon: the polarization and two of the orbital angular momentum states. We demonstrate how to implement this physically and what components would be needed. We then illustrate some of the results that could be obtained by performing the experiment.