| The Aharonov-Bohm (AB) effect, and its charge-spin dual, the Aharonov-Casher (AC) effect, have been beautifully demonstrated in experiments of transport through mesoscopic rings. Although these phenomena can be fully explained within the non-interacting picture, the situation is much more complicated when electronic interactions are present. In this talk I will present some theoretical results for a situation when the AB and AC effects take place simultaneously in a ring with embedded quantum dots (QDs). Due to strong Coulomb repulsion, and for an odd number of electrons, a QD can have a localized magnetic moment. At very low temperatures, the (antiferromagnetic) exchange interaction between the magnetic moment and the spin of conduction electrons, leads to a many-body phenomenon known as Kondo effect. Our results suggest that as a consequence of the interplay between Kondo and interference effects, very modest electric and magnetic fields can lead to spin-polarized transport with a significant degree of polarization. |
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