35 research outputs found
Coulomb blockade conductance peak fluctuations in quantum dots and the independent particle model
We study the combined effect of finite temperature, underlying classical
dynamics, and deformations on the statistical properties of Coulomb blockade
conductance peaks in quantum dots. These effects are considered in the context
of the single-particle plus constant-interaction theory of the Coulomb
blockade. We present numerical studies of two chaotic models, representative of
different mean-field potentials: a parametric random Hamiltonian and the smooth
stadium. In addition, we study conductance fluctuations for different
integrable confining potentials. For temperatures smaller than the mean level
spacing, our results indicate that the peak height distribution is nearly
always in good agreement with the available experimental data, irrespective of
the confining potential (integrable or chaotic). We find that the peak bunching
effect seen in the experiments is reproduced in the theoretical models under
certain special conditions. Although the independent particle model fails, in
general, to explain quantitatively the short-range part of the peak height
correlations observed experimentally, we argue that it allows for an
understanding of the long-range part.Comment: RevTex 3.1, 34 pages (including 13 EPS and PS figures), submitted to
Phys. Rev.