Photonic Discrete-time Quantum Walks and Applications

TL;DR

This paper reviews photonic implementations of discrete-time quantum walks and introduces a novel scheme using spatial modes and SLMs, enabling flexible simulation of quantum walk steps for applications in quantum simulation and entanglement.

Contribution

The paper presents a new photonic DTQW scheme utilizing transverse spatial modes and programmable SLMs, allowing arbitrary step simulation beyond previous mode-multiplexed methods.

Findings

Proposed a flexible photonic DTQW scheme with arbitrary step simulation.

Reviewed current applications in quantum simulation of topological effects.

Discussed use of non-local coin operations with two-photon entanglement.

Abstract

We present a review of photonic implementations of discrete-time quantum walks (DTQW) in the spatial and temporal domains, based on spatial- and time-multiplexing techniques, respectively. Additionally, we propose a detailed novel scheme for photonic DTQW, using transverse spatial modes of single photons and programmable spatial light modulators (SLM) to manipulate them. Unlike all previous mode-multiplexed implementations, this scheme enables simulation of an arbitrary step of the walker, only limited, in principle, by the SLM resolution. We discuss current applications of such photonic DTQW architectures in quantum simulation of topological effects and the use of non-local coin operations based on two-photon hybrid entanglement.