Weak localization and conductance fluctuations in a quantum dot with parallel magnetic field and spin-orbit scattering

TL;DR

This paper investigates how spin-orbit scattering and magnetic fields influence conductance in a chaotic quantum dot, revealing complex behaviors and providing methods to measure spin-orbit coupling parameters.

Contribution

It calculates the weak localization correction and conductance covariance considering both magnetic field orientations and spin-orbit effects, introducing new insights into conductance behavior.

Findings

Magnetoconductance component is anti-symmetric due to in-plane magnetic field and spin-orbit scattering.

Spin-orbit scattering causes a magnetic-field echo in conductance autocorrelation.

Results enable measurement of spin-orbit scattering lengths in GaAs heterostructures.

Abstract

In the presence of both spin-orbit scattering and a magnetic field the conductance of a chaotic GaAs quantum dot displays quite a rich behavior. Using a Hamiltonian derived by Aleiner and Falko [Phys. Rev. Lett. 87, 256801 (2001)] we calculate the weak localization correction and the covariance of the conductance, as a function of parallel and perpendicular magnetic field and spin-orbit coupling strength. We also show how the combination of an in-plane magnetic field and spin-orbit scattering gives rise to a component to the magnetoconductance that is anti-symmetric with respect to reversal of the perpendicular component of the magnetic field and how spin-orbit scattering leads to a "magnetic-field echo" in the conductance autocorrelation function. Our results can be used for a measurement of the Dresselhaus and Bychkov-Rashba spin-orbit scattering lengths in a GaAs/GaAlAs heterostructure.