Magnetic Field Induced Charge Instabilities in Weakly Coupled Superlattices

TL;DR

This paper investigates how high magnetic fields induce charge instabilities and electric field domains in weakly coupled doped superlattices, revealing new unstable regions and stable branches in the I-V characteristics.

Contribution

It introduces a time-dependent self-consistent model to analyze charge instabilities and electric field domain formation under high magnetic fields in superlattices.

Findings

Charge instabilities lead to electric field domains.

High magnetic fields create new negative differential conductance regions.

Additional stable branches appear in the I-V curves.

Abstract

Using a time dependent selfconsistent model for vertical sequential tunneling,we study the appearance of charge instabilities that lead to the formation of electric field domains in a weakly coupled doped superlattice in the presence of high magnetic fields parallel to the transport direction. The interplay between the high non linearity of the system --coming from the Coulomb interaction-- and the inter-Landau-level scattering at the domain walls (regions of charge accumulation inside the superlattice) gives rise to new unstable negative differential conductance regions and extra stable branches in the sawtooth-like I-V curves.