Quenched and negative Hall effect in periodic media: application to antidot superlattices
نویسنده
چکیده
We find the counterintuitive result that electrons move in opposite direction to the free electron E × B-drift when subject to a two-dimensional periodic potential. We show that this phenomenon arises from chaotic channeling trajectories and by a subtle mechanism leads to a negative value of the Hall resistivity for small magnetic fields. The effect is present also in experimentally recorded Hall curves in antidot arrays on semiconductor heterojunctions but so far has remained unexplained. PACS numbers: 73.40.L, 05.45, 73.20.M Europhysics Letters, in press. Typeset using REVTEX
منابع مشابه
Graphene Optoelectronics based on Antidot Superlattices
Graphene is well known for its outstanding electronic, thermal, and mechanical properties, and has recently gained tremendous interest as a nanomaterial for optoelectronic devices. We review our recent efforts on exfoliated graphene with a particular focus on the influence of graphene’s chiral edges on the electronic and optical properties. We first show that Raman spectroscopy can not only be ...
متن کاملPhase–coherence Effects in Antidot Lattices: A Semiclassical Approach to Bulk Conductivity
We derive semiclassical expressions for the Kubo conductivity tensor. Within our approach the oscillatory parts of the diagonal and Hall conductivity are given as sums over contributions from classical periodic orbits in close relation to Gutzwiller’s trace formula for the density of states. Taking into account the effects of weak disorder and temperature we reproduce recently observed anomalou...
متن کاملLocalized States and resultant band bending in graphene antidot superlattices.
We fabricated dye sensitized graphene antidot superlattices with the purpose of elucidating the role of the localized edge state density. The fluorescence from deposited dye molecules was found to strongly quench as a function of increasing antidot filling fraction, whereas it was enhanced in unpatterned but electrically backgated samples. This contrasting behavior is strongly indicative of a b...
متن کاملCompeting anisotropies in exchange-biased nanostructured thin films
The magnetic anisotropies of a patterned, exchange biased Fe50Mn50/Ni80Fe20 system are studied using ferromagnetic resonance, supplemented by Brillouin light scattering experiments and Kerr magnetometry. The exchange biased bilayer is partially etched into an antidot geometry so that the system approximates a Ni80Fe20 layer in contact with antidot structured Fe50Mn50. Brillouin light scattering...
متن کاملElectron interactions in an antidot in the integer quantum Hall regime
A quantum antidot, a submicron depletion region in a two-dimensional electron system, has been actively studied in the past two decades, providing a powerful tool for understanding quantum Hall systems. In a perpendicular magnetic field, electrons form bound states around the antidot. Aharonov-Bohm resonances through such bound states have been experimentally studied, showing interesting phenom...
متن کامل