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arXiv · 1312.4686

Finite-frequency-dependent noise of a quantum dot in a magnetic field

Catalin Pascu Moca·Pascal Simon·Chung-Hou Chung·Gergely Zarand
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Abstract

We present a detailed study for the finite-frequency current noise of a Kondo quantum dot in presence of a magnetic field by using a recently developed real time functional renormalization group approach [Phys. Rev. B $\mathbf{83}$, 201303(R) (2011)]. The scaling equations are modified in an external magnetic field; the couplings and non-local current vertices become strongly anisotropic, and develop new singularities. Consequently, in addition to the natural emission threshold frequency, $\hbarω= |eV|$, a corresponding singular behavior is found to emerge in the noise spectrum at frequencies $\hbar ω\approx |eV\pm B|$. The predicted singularities are measurable with present-day experimental techniques.

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Catalin Pascu Moca, Pascal Simon, Chung-Hou Chung, Gergely Zarand. 2014-04-17. Finite-frequency-dependent noise of a quantum dot in a magnetic field. https://doi.org/10.1103/physrevb.89.155138

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