Imaging backscattering through impurity-induced antidots in quantum Hall constrictions
Mesoscale and Nanoscale Physics
2012-10-24 v1 Quantum Physics
Abstract
We exploit the biased tip of a scanning gate microscope (SGM) to induce a controlled backscattering between counter-propagating edge channels in a wide constriction in the quantum Hall regime. We compare our detailed conductance maps with a numerical percolation model and demonstrate that conductance fluctuations observed in these devices as a function of the gate voltage originate from backscattering events mediated by localized states pinned by potential fluctuations. Our imaging technique allows us to identify the necessary conditions for the activation of these backscattering processes and also to reconstruct the constriction confinement potential profile and the underlying disorder.
Cite
@article{arxiv.1209.2438,
title = {Imaging backscattering through impurity-induced antidots in quantum Hall constrictions},
author = {Nicola Paradiso and Stefan Heun and Stefano Roddaro and Giorgio Biasiol and Lucia Sorba and Davide Venturelli and Fabio Taddei and Vittorio Giovannetti and Fabio Beltram},
journal= {arXiv preprint arXiv:1209.2438},
year = {2012}
}