摘要Using the Keldysh nonequilibrium Green function and equation-of-motion technique, we investigate Fano versus Kondo resonances in a closed Aharonov--Bohm interferometer coupled to ferromagnetic leads and study their effects on the conductance of this system. The conductance with both parallel and antiparallel lead-polarization alignments is analysed for various values of the magnetic flux. Our results show that this system can provide an excellent spin filtering property, and a large tunnelling magnetoresistance can arise by adjusting the system parameters, which indicates that this system is a possible candidate for spin valve transistors and has important applications in spintronics.
Abstract：Using the Keldysh nonequilibrium Green function and equation-of-motion technique, we investigate Fano versus Kondo resonances in a closed Aharonov--Bohm interferometer coupled to ferromagnetic leads and study their effects on the conductance of this system. The conductance with both parallel and antiparallel lead-polarization alignments is analysed for various values of the magnetic flux. Our results show that this system can provide an excellent spin filtering property, and a large tunnelling magnetoresistance can arise by adjusting the system parameters, which indicates that this system is a possible candidate for spin valve transistors and has important applications in spintronics.
WU Shao-Quan;SUN Wei-Li. Fano versus Kondo Resonances in a Closed Aharonov--Bohm Interferometer Coupled to Ferromagnetic Electrodes[J]. 中国物理快报, 2007, 24(4): 1054-1057.
WU Shao-Quan, SUN Wei-Li. Fano versus Kondo Resonances in a Closed Aharonov--Bohm Interferometer Coupled to Ferromagnetic Electrodes. Chin. Phys. Lett., 2007, 24(4): 1054-1057.
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2007, Vol. 24 
