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Ground state spin and Coulomb blockade peak motion in chaotic quantum dots

J. A. Folk·C. M. Marcus·R. Berkovits·I. L. Kurland·I. L. Aleiner·B. L. Altshuler
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Abstract

We investigate experimentally and theoretically the behavior of Coulomb blockade (CB) peaks in a magnetic field that couples principally to the ground-state spin (rather than the orbital moment) of a chaotic quantum dot. In the first part, we discuss numerically observed features in the magnetic field dependence of CB peak and spacings that unambiguously identify changes in spin S of each ground state for successive numbers of electrons on the dot, N. We next evaluate the probability that the ground state of the dot has a particular spin S, as a function of the exchange strength, J, and external magnetic field, B. In the second part, we describe recent experiments on gate-defined GaAs quantum dots in which Coulomb peak motion and spacing are measured as a function of in-plane magnetic field, allowing changes in spin between N and N+1 electron ground states to be inferred.

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J. A. Folk, C. M. Marcus, R. Berkovits, I. L. Kurland, I. L. Aleiner, B. L. Altshuler. 2000-10-27. Ground state spin and Coulomb blockade peak motion in chaotic quantum dots. https://doi.org/10.1238/physica.topical.090a00026

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