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Frequency-Dependent Current Noise through Quantum-Dot Spin Valves

Matthias Braun·Jürgen König·Jan Martinek
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Abstract

We study frequency-dependent current noise through a single-level quantum dot connected to ferromagnetic leads with non-collinear magnetization. We propose to use the frequency-dependent Fano factor as a tool to detect single-spin dynamics in the quantum dot. Spin precession due to an external magnetic and/or a many-body exchange field affects the Fano factor of the system in two ways. First, the tendency towards spin-selective bunching of the transmitted electrons is suppressed, which gives rise to a reduction of the low-frequency noise. Second, the noise spectrum displays a resonance at the Larmor frequency, whose lineshape depends on the relative angle of the leads' magnetizations.

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Matthias Braun, Jürgen König, Jan Martinek. 2006-01-17. Frequency-Dependent Current Noise through Quantum-Dot Spin Valves. https://doi.org/10.1103/physrevb.74.075328

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