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Theory of Transport through Quantum-Dot Spin Valves in the Weak-Coupling Regime

Matthias Braun·Jürgen König·Jan Martinek
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Abstract

We develop a theory of electron transport through quantum dots that are weakly coupled to ferromagnetic leads. The theory covers both the linear and nonlinear transport regime, takes non-collinear magnetization of the leads into account, and allows for an externally-applied magnetic field. We derive generalized rate equations for the dot's occupation and accumulated spin and discuss the influence of the dot's spin on the transmission. A negative differential conductance and a nontrivial dependence of the conductance on the angle between the lead magnetizations is predicted.

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Matthias Braun, Jürgen König, Jan Martinek. 2004-12-08. Theory of Transport through Quantum-Dot Spin Valves in the Weak-Coupling Regime. https://doi.org/10.1103/physrevb.70.195345

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