Bloch-Landau-Zener dynamics induced by a synthetic field in a photonic quantum walk

TL;DR

This paper demonstrates a photonic quantum walk under a synthetic gauge field, revealing complex dynamics such as Bloch oscillations and Landau-Zener transitions, with potential implications for topological quantum systems.

Contribution

It introduces a novel experimental setup for photonic quantum walks with synthetic gauge fields, exploring the interplay of Bloch-Landau-Zener dynamics in Floquet systems.

Findings

Ballistic spreading observed when energy gaps are small.

Controlled tuning of system dynamics via gap manipulation.

Insights into Floquet topological phenomena in photonic systems.

Abstract

Quantum walks are processes that model dynamics in coherent systems. Their experimental implementations proved key to unveil novel phenomena in Floquet topological insulators. Here we realize a photonic quantum walk in the presence of a synthetic gauge field, which mimics the action of an electric field on a charged particle. By tuning the energy gaps between the two quasi-energy bands, we investigate intriguing system dynamics characterized by the interplay between Bloch oscillations and Landau-Zener transitions. When both gaps at quasi-energy values 0 and $\pi$ are vanishingly small, the Floquet dynamics follows a ballistic spreading.