Spectral scrambling in Coulomb-blockade quantum dots

Y. Alhassid; Yuval Gefen

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arXiv · cond-mat/0101461

Spectral scrambling in Coulomb-blockade quantum dots

Y. Alhassid·Yuval Gefen

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Abstract

We study the fluctuations of an energy level as a function of the number of electrons $m$ added to a Coulomb-blockade quantum dot. A microscopic calculation in the limit of Koopmans' theorem predicts that the standard deviation of these fluctuations behaves as $\sqrt{m}$ in the absence of surface charge but is linear in $m$ when the effect of a surface charge in a finite geometry is included. The microscopic results are compared to a parametric random-matrix approach. We estimate the number of electrons it takes to scramble the spectrum completely in terms of the interaction strength, the dimensionless Thouless conductance, and the symmetry class.

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Y. Alhassid, Yuval Gefen. 2001-08-22. Spectral scrambling in Coulomb-blockade quantum dots. https://arxiv.org/abs/cond-mat/0101461

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