Quantum walks in two dimensions: controlling directional spreading with entangling coins and tunable disordered step operator

TL;DR

This paper explores two-dimensional disordered quantum walks with entangling coins and tunable disorder, demonstrating controllable spreading and entanglement, and highlighting the impact of dimensionality on quantum information transport.

Contribution

It introduces a 2-D disordered quantum walk model with entangling coins and tunable disorder, revealing controllable spreading and entanglement properties.

Findings

Disorder in one direction controls spreading in the other.

Quantum walks act as tunable decoherence channels.

Dimensionality influences quantum transport and information.

Abstract

We study a 2-D disordered time-discrete quantum walk based on 1-D `generalized elephant quantum walk' where an entangling coin operator is assumed and which paves the way to a new set of properties. We show that considering a given disorder in one direction, it is possible to control the degree of spreading and entanglement in the other direction. This observation helps assert that the random quantum walks of this ilk serve as a controllable decoherence channel with the degree of randomness being the tunable parameter and highlight the role of dimensionality in quantum systems regarding information and transport.