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Zeeman smearing of the Coulomb blockade

Karyn Le Hur
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Abstract

Charge fluctuations of a large quantum dot coupled to a two-dimensional lead via a single-mode good Quantum Point Contact (QPC) and capacitively coupled to a back-gate, are investigated in the presence of a parallel magnetic field. The Zeeman term induces an asymmetry between transmission probabilities for the spin-up and spin-down channels at the QPC, producing noticeable effects on the quantization of the grain charge already at low magnetic fields. Performing a quantitative analysis, I show that the capacitance between the gate and the lead exhibits - instead of a logarithmic singularity - a reduced peak as a function of gate voltage. Experimental applicability is discussed.

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Karyn Le Hur. 2001-11-07. Zeeman smearing of the Coulomb blockade. https://doi.org/10.1103/physrevb.64.161302

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