Electric quantum walks with individual atoms

TL;DR

This paper demonstrates the experimental realization of electric quantum walks using individual atoms, revealing quantum phenomena like Bloch oscillations, interband tunneling, and behaviors under strong fields such as resonances and localization.

Contribution

The study introduces a novel method to implement electric fields in quantum walks with atoms, enabling exploration of complex quantum behaviors in lattice systems.

Findings

Observation of Bloch oscillations and interband tunneling.

Identification of quantum resonances and dynamical localization.

Behavior differences under strong electric fields.

Abstract

We report on the experimental realization of electric quantum walks, which mimic the effect of an electric field on a charged particle in a lattice. Starting from a textbook implementation of discrete-time quantum walks, we introduce an extra operation in each step to implement the effect of the field. The recorded dynamics of such a quantum particle exhibits features closely related to Bloch oscillations and interband tunneling. In particular, we explore the regime of strong fields, demonstrating contrasting quantum behaviors: quantum resonances vs. dynamical localization depending on whether the accumulated Bloch phase is a rational or irrational fraction of 2\pi.