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Effect of the Kondo correlation on Shot Noise in a Quantum Dot

Bing Dong·X. L. Lei
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Abstract

The current noise in a quantum dot coupled to two leads is investigated in the Kondo regime with and without the influence of magnetic fields by employing a finite-$U$ slave-boson mean field theory to calculate the current-current correlation function at zero temperature. The numerical results show that, depending on the energy level of the QD the Coulomb interactin may reduce or enhance the zero-frequency shot noise power spectrum in comparison with that without Coulomb interaction. But the Fano factor is always reduced significantly due to the Kondo-correlation effect, and the most pronounced suppression appears at the electron-hole symmetry case $2ε_d+U=0$. In addition, the application of a magnetic field enhance the Fano factor of the shot noise at small external voltage, which is attributed to the reduction of the Kondo-enhanced density-of-state and transmission probability in a quantum dot.

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Bing Dong, X. L. Lei. 2002-04-10. Effect of the Kondo correlation on Shot Noise in a Quantum Dot. https://doi.org/10.1088/0953-8984%2F14%2F19%2F318

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