Spatially confined Bloch oscillations in semiconductor superlattices

TL;DR

This paper investigates how Bloch oscillations can persist in semiconductor superlattices with minimal damping, showing they can be stable and spatially confined under certain conditions, with implications for electronic transport.

Contribution

It demonstrates the existence of stable, spatially confined Bloch oscillations in superlattices with long scattering times, highlighting the role of nonlinearities in their persistence.

Findings

Bloch oscillations can be stable and confined near the collector.

Damping due to inelastic collisions suppresses Bloch oscillations.

Numerical solutions reveal inhomogeneous profiles in the superlattice.

Abstract

In a semiconductor superlattice with long scattering times, damping of Bloch oscillations due to scattering is so small that convective nonlinearities may compensate it and Bloch oscillations persist even in the hydrodynamic regime. In this case, numerical solutions show that there are stable Bloch oscillations confined to a region near the collector with inhomogeneous field, charge, current density and energy density profiles. These Bloch oscillations disappear when damping due to inelastic collisions becomes sufficiently strong.