Enhanced non-Markovian behavior in quantum walks with Markovian disorder

TL;DR

This paper demonstrates that disorder in quantum walks enhances non-Markovian effects, such as information backflow, and links these effects to localization phenomena and other quantum properties.

Contribution

It reveals that uncorrelated disorder amplifies non-Markovian behavior in quantum walks and connects this to localization and quantum correlations.

Findings

Disorder enhances information backflow in quantum walks.

Localization effects are linked to increased non-Markovianity.

Quantum properties like entanglement are affected by disorder.

Abstract

Non-Markovian quantum effects are typically observed in systems interacting with structured reservoirs. Discrete-time quantum walks are prime example of such systems in which, quantum memory arises due to the controlled interaction between the coin and position degrees of freedom. Here we show that the information backflow that quantifies memory effects can be enhanced when the particle is subjected to uncorrelated static or dynamic disorder. The presence of disorder in the system leads to localization effects in 1-dimensional quantum walks. We shown that it is possible to infer about the nature of localization in position space by monitoring the information backflow in the reduced system. Further, we study other useful properties of quantum walk such as entanglement, interference and its connection to quantum non-Markovianity.