Giant resonant skew scattering of plasma waves in a two-dimensional electron gas

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Finnigan, Cooper, Efimkin, Dmitry K.
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916373435777024
author Finnigan, Cooper
Efimkin, Dmitry K.
author_facet Finnigan, Cooper
Efimkin, Dmitry K.
contents Electron skew scattering by impurities is one of the major mechanisms behind the anomalous Hall effect in ferromagnetic nanostructures. It is particularly strong at the surface of topological insulators where electron dynamics is governed by the spin-1/2 Dirac equation. Motivated by recently discovered mappings between hydrodynamics and the spin-1 Dirac equation, we consider the scattering of plasma waves -- propagating charge density oscillations -- excited in graphene off a non-uniform magnetic field created by an adjacent circular micromagnet. The calculated scattering amplitude not only exhibits a giant asymmetry, or skewness, but is resonantly enhanced if the frequency of the incoming wave matches the frequency of the chiral trapped mode circulating the micromagnet in only one direction. Furthermore, if the frequency of the incoming plasma wave is a few times larger than the Larmor frequency, the angular distribution of its forward scattering is almost indistinguishable from that of a Dirac electron at the surface of a topological insulator scattering off a magnetic impurity. The micrometer scale of the proposed setup enables direct investigations of individual skew scattering events previously inaccessible in electronic systems.
format Preprint
id arxiv_https___arxiv_org_abs_2402_16263
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Giant resonant skew scattering of plasma waves in a two-dimensional electron gas
Finnigan, Cooper
Efimkin, Dmitry K.
Mesoscale and Nanoscale Physics
Electron skew scattering by impurities is one of the major mechanisms behind the anomalous Hall effect in ferromagnetic nanostructures. It is particularly strong at the surface of topological insulators where electron dynamics is governed by the spin-1/2 Dirac equation. Motivated by recently discovered mappings between hydrodynamics and the spin-1 Dirac equation, we consider the scattering of plasma waves -- propagating charge density oscillations -- excited in graphene off a non-uniform magnetic field created by an adjacent circular micromagnet. The calculated scattering amplitude not only exhibits a giant asymmetry, or skewness, but is resonantly enhanced if the frequency of the incoming wave matches the frequency of the chiral trapped mode circulating the micromagnet in only one direction. Furthermore, if the frequency of the incoming plasma wave is a few times larger than the Larmor frequency, the angular distribution of its forward scattering is almost indistinguishable from that of a Dirac electron at the surface of a topological insulator scattering off a magnetic impurity. The micrometer scale of the proposed setup enables direct investigations of individual skew scattering events previously inaccessible in electronic systems.
title Giant resonant skew scattering of plasma waves in a two-dimensional electron gas
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2402.16263