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arXiv · 1105.1478

Full counting statistics for SU(N) impurity Anderson model

Rui Sakano·Akira Oguri·Takeo Kato·Seigo Tarucha
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Abstract

We analyze the full counting statistics of a multiorbital Kondo effect in a quantum dotwith the SU(N) symmetry in the framework of the renormalized perturbation theory. The current probability distribution function is calculated for an arbitrary dot-site Coulomb repulsion $U$ in the particle-hole symmetric case. The resulting cumulant up to the leading nonlinear term of applied bias voltages indicates two types of electron transfer, respectively carrying charge $e$ and $2e$, with different $N$-dependences. The cross correlation between different orbital currents shows exponential enhancement with respect to $U$, which directly addresses formation of the orbital-singlet state.

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Rui Sakano, Akira Oguri, Takeo Kato, Seigo Tarucha. 2012-06-27. Full counting statistics for SU(N) impurity Anderson model. https://doi.org/10.1103/physrevb.83.241301

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