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Spin filtering and magnetoresistance in ballistic tunnel junctions

J. C. Egues·C. Gould·G. Richter·L. W. Molenkamp
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Abstract

We theoretically investigate magnetoresistance (MR) effects in connection with spin filtering in quantum-coherent transport through tunnel junctions based on non-magnetic/semimagnetic heterostructures. We find that spin filtering in conjunction with the suppression/enhancement of the spin-dependent Fermi seas in semimagnetic contacts gives rise to (i) spin-split kinks in the MR of single barriers and (ii) a robust beating pattern in the MR of double barriers with a semimagnetic well. We believe these are unique signatures for quantum filtering.

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J. C. Egues, C. Gould, G. Richter, L. W. Molenkamp. 2001-10-19. Spin filtering and magnetoresistance in ballistic tunnel junctions. https://doi.org/10.1103/physrevb.64.195319

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