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arXiv · 1010.2729

Spin-polarized currents in double and triple quantum dots driven by ac magnetic fields

Maria Busl·Gloria Platero
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Abstract

We analyze transport through both a double quantum dot and a triple quantum dot with inhomogeneous Zeeman splittings in the presence of crossed dc and ac magnetic fields. We find that strongly spin-polarized current can be achieved by tuning the relative energies of the Zeeman-split levels of the dots, by means of electric gate voltages: depending on the energy level detuning, the double quantum dot works either as spin-up or spin-down filter. We show that a triple quantum dot in series under crossed dc and ac magnetic fields can act not only as spin-filter but also as spin-inverter.

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Maria Busl, Gloria Platero. 2010-10-13. Spin-polarized currents in double and triple quantum dots driven by ac magnetic fields. https://doi.org/10.1103/physrevb.82.205304

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