Decoherent quantum walks driven by a generic coin operation

TL;DR

This paper investigates how different types of noise, including bit-flip and topological disruptions, affect the behavior of quantum walks on a linear chain, revealing key differences and similarities in their decoherent dynamics.

Contribution

It introduces a comparative analysis of decoherence effects from generic coin operation noise and topological noise in quantum walks.

Findings

Bit-flip noise causes decoherence in the coin subspace.

Topological noise from broken links impacts walk dynamics differently.

Decoherence effects depend on the probability of noise events.

Abstract

We consider the effect of different unitary noise mechanisms on the evolution of a quantum walk (QW) on a linear chain with a generic coin operation: (i) bit-flip channel noise, restricted to the coin subspace of the QW, and (ii) topological noise caused by randomly broken links in the linear chain. Similarities and differences in the respective decoherent dynamics of the walker as a function of the probability per unit time of a decoherent event taking place are discussed.