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Spin-Dependent Transport through the Finite Array of Quantum Dots: Spin Gun

S. A. Avdonin·L. A. Dmitrieva·Yu. A. Kuperin·V. V. Sartan
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Abstract

The problem of spin-dependent transport of electrons through a finite array of quantum dots attached to 1D quantum wire (spin gun) for various semiconductor materials is studied. The Breit-Fermi term for spin-spin interaction in the effective Hamiltonian of the device is shown to result in a dependence of transmission coefficient on the spin orientation. The difference of transmission probabilities for singlet and triplet channels can reach few percent for a single quantum dot. For several quantum dots in the array due to interference effects it can reach approximately 100% for some energy intervals. For the same energy intervals the conductance of the device reaches the value $\approx 1$ in $[e^{2}/π\hbar]$ units. As a result a model of the spin-gun which transforms the spin-unpolarized electron beam into completely polarized one is suggested.

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S. A. Avdonin, L. A. Dmitrieva, Yu. A. Kuperin, V. V. Sartan. 2003-11-18. Spin-Dependent Transport through the Finite Array of Quantum Dots: Spin Gun. https://arxiv.org/abs/cond-mat/0310632

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