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arXiv · 1008.0150

Non-equilibrium frequency-dependent noise through a quantum dot: A real time functional renormalization group approach

C. P. Moca·P. Simon·C. H. Chung·G. Zarand
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Abstract

We construct a real time current-conserving functional renormalization group (RG) scheme on the Keldysh contour to study frequency-dependent transport and noise through a quantum dot in the local moment regime. We find that the current vertex develops a non-trivial non-local structure in time, governed by a new set of RG equations. Solving these RG equations, we compute the complete frequency and temperature-dependence of the noise spectrum. For voltages large compared to the Kondo temperature, $eV \gg k_BT_K$, two sharp anti-resonances are found in the noise spectrum at frequencies $\hbar ω= \pm e V$, and correspondingly, two peaks in the ac conductance through the dot.

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C. P. Moca, P. Simon, C. H. Chung, G. Zarand. 2010-08-01. Non-equilibrium frequency-dependent noise through a quantum dot: A real time functional renormalization group approach. https://doi.org/10.1103/physrevb.83.201303

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