Coherent tunnelling across a quantum point contact in the quantum Hall regime
Abstract
The unique properties of quantum Hall devices arise from the ideal one-dimensional edge states that form in a two-dimensional electron system at high magnetic field. Tunnelling between edge states across a quantum point contact (QPC) has already revealed rich physics, like fractionally charged excitations, or chiral Luttinger liquid. Thanks to scanning gate microscopy, we show that a single QPC can turn into an interferometer for specific potential landscapes. Spectroscopy, magnetic field and temperature dependences of electron transport reveal a quantitatively consistent interferometric behavior of the studied QPC. To explain this unexpected behavior, we put forward a new model which relies on the presence of a quantum Hall island at the centre of the constriction as well as on different tunnelling paths surrounding the island, thereby creating a new type of interferometer. This work sets the ground for new device concepts based on coherent tunnelling.
Keywords
Cite
@article{arxiv.1305.1589,
title = {Coherent tunnelling across a quantum point contact in the quantum Hall regime},
author = {F. Martins and S. Faniel and B. Rosenow and H. Sellier and S. Huant and M. G. Pala and L. Desplanque and X. Wallart and V. Bayot and B. Hackens},
journal= {arXiv preprint arXiv:1305.1589},
year = {2013}
}
Comments
19 pages, 8 figures