# Quelques mécanismes non conventionnels de l'effet Hall anormal

Abstract : This thesis is divided in three distinct parts. In the first and
second parts, we speak about unconventional mechanisms of the
Anomalous Hall Effect (AHE). The first part gives a short review of
the conventional and unconventional mechanisms of the AHE (chapter~1).
chapter~2 is devoted to geometrical phases.

The second part of this thesis answer to some questions about the AHE.
The third chapter treats the role of impurities in intrinsic mechanism
of the AHE. By calculating of the off-diagonal conductivity in the
linear response theory for a model of 2DEG in presence of spin-orbit
coupling, we obtained two contributions related to the diffusion of
electrons by impurities of defaults but independent of the
concentration of impurities. The second one is the Karplus and
Luttinger term, which depends on the topology of the energy band. In
the chapter~4, we propose an experimental setup based on 2DEG in
presence of inhomogeneous magnetic field created by magnetic
nanostructure. In this system, the Hall conductivity has discontinuous
variations related to the topology of the magnetic field, which can be
modified by applying an additional constant magnetic field. In the
chapter~5, we study the spin chirality mechanism of the AHE on the
kagome lattice and discuss the results of recent experiments on the
pyrochlore compound Nd$_2$Mo$_2$O$_7$.

The last part of this thesis is devoted to electron dynamic in
inhomogeneous magnetic field. The chapters~6 and~7 give a introduction
of electrons dynamic in two dimensional periodic magnetic field. The
last chapter is a study of electron dynamic in 2D periodic magnetic
field. We find that it exists persistent currents related to
localization of electrons around the regions where the magnetic field
is canceling.
Keywords :
Document type :
Theses
Domain :

Cited literature [91 references]

https://tel.archives-ouvertes.fr/tel-00012052
Contributor : Mathieu Taillefumier <>
Submitted on : Tuesday, March 28, 2006 - 4:44:49 PM
Last modification on : Friday, December 18, 2020 - 1:22:02 PM
Long-term archiving on: : Monday, September 17, 2012 - 1:10:32 PM

### Identifiers

• HAL Id : tel-00012052, version 1

### Citation

Mathieu Taillefumier. Quelques mécanismes non conventionnels de l'effet Hall anormal. Physique mathématique [math-ph]. Université Joseph-Fourier - Grenoble I, 2006. Français. ⟨tel-00012052⟩

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