Floquet-Bloch Oscillations and Intraband Zener Tunneling in an Oblique Spacetime Crystal

TL;DR

This paper explores the unique electronic behaviors in an oblique spacetime crystal, revealing novel Floquet-Bloch oscillations and intraband Zener tunneling, with implications for quantum acoustoelectric energy conversion.

Contribution

It provides a systematic analysis of the band structure and uncovers new topological phenomena and tunneling effects in an oblique spacetime crystal.

Findings

Revealed unique band topologies leading to Floquet-Bloch oscillations.

Discovered intraband Zener tunneling beyond the adiabatic limit.

Proposed a quantum acoustoelectric generator concept.

Abstract

We investigate an oblique spacetime crystal realized by a monoatomic crystal in which a mode of sound propagates. We provide a systematic analysis of the crystal and obtain the corresponding band structure, based on which the electron dynamics under an external electric field is studied. Several unique band topologies are revealed, which lead to novel Floquet-Bloch oscillations in the electron's motion. We also discover intraband Zener tunneling in the oblique spacetime crystal beyond the adiabatic limit, which effectively converts between the different band topologies. Our results indicate the possibility of a prototypical quantum acoustoelectric generator that converts energy between the sound wave and a DC electric field in quantized units.