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Weak localization and conductance fluctuations of a chaotic quantum dot with tunable spin-orbit coupling

P. W. Brouwer·J. N. H. J. Cremers·B. I. Halperin
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Abstract

In a two-dimensional quantum dot in a GaAs heterostructure, the spin-orbit scattering rate is substantially reduced below the rate in a bulk two-dimensional electron gas [B.I. Halperin et al, Phys. Rev. Lett. 86, 2106 (2001)]. Such a reduction can be undone if the spin-orbit coupling parameters acquire a spatial dependence, which can be achieved, e.g., by a metal gate covering only a part of the quantum dot. We calculate the effect of such spatially non-uniform spin-orbit scattering on the weak localization correction and the universal conductance fluctuations of a chaotic quantum dot coupled to electron reservoirs by ballistic point contacts, in the presence of a magnetic field parallel to the plane of the quantum dot.

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P. W. Brouwer, J. N. H. J. Cremers, B. I. Halperin. 2001-10-23. Weak localization and conductance fluctuations of a chaotic quantum dot with tunable spin-orbit coupling. https://doi.org/10.1103/physrevb.65.081302

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