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

Jan-Hein Cremers·Piet W. Brouwer·Vladimir I. Falko
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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.

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Jan-Hein Cremers, Piet W. Brouwer, Vladimir I. Falko. 2003-04-09. Weak localization and conductance fluctuations in a quantum dot with parallel magnetic field and spin-orbit scattering. https://doi.org/10.1103/physrevb.68.125329

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