Quantum Paths: a Quantum Walk approach

TL;DR

This paper introduces a quantum walk-based method to emulate the quantum switch using spatial superposition of channels, potentially offering a more practical approach to achieve noiseless quantum communication.

Contribution

It presents a novel theoretical framework applying quantum random walks to replicate quantum switch behavior via spatial superposition of channels.

Findings

Quantum walk framework can simulate quantum switch outputs.

Spatial superposition enhances channel capacity.

Potential for more practical quantum switch implementation.

Abstract

The quantum switch, a process enabling a coherent superposition of different orders of quantum channels, has garnered significant attention due to its ability to enable noiseless communications through noisy channels, such as entanglement-breaking channels. However, its practical implementation and scalability remain challenging. In contrast, the spatial superposition of quantum channels is more accessible experimentally and has been shown to enhance channel capacity, although it does not match the performance of the quantum switch. In this work, we present preliminary theoretical results demonstrating that, by applying tools of the quantum random walk framework to the spatial superposition of channels, it is possible to replicate the output of a quantum switch. These findings suggest a promising and more feasible route to emulate the quantum switch, offering both practical advantages and interpretative clarity.