By means of the slave-boson mean-field approximation, we theoretically investigate the Kondo and Coulomb interaction effects in spin-polarized transport through two coupled quantum dots coupled to two ferromagnetic leads by the Anderson Hamiltonian. The density of states is calculated in the Kondo regime for the effect of the interdot Coulomb repulsion with both parallel and antiparallel lead-polarization alignments. Our results reveal that the interdot Coulomb interaction between quantum dots greatly influence the density of states of the dots. We then clarify relevant underlying physics of this problem.
By means of the slave-boson mean-field approximation, we theoretically investigate the Kondo and Coulomb interaction effects in spin-polarized transport through two coupled quantum dots coupled to two ferromagnetic leads by the Anderson Hamiltonian. The density of states is calculated in the Kondo regime for the effect of the interdot Coulomb repulsion with both parallel and antiparallel lead-polarization alignments. Our results reveal that the interdot Coulomb interaction between quantum dots greatly influence the density of states of the dots. We then clarify relevant underlying physics of this problem.
[1] Ono K, Austing D G, Tokura Y and Tarucha S 2002 Science 297 1313 [2] Van der Wiel W G, Franceschi S De, Elzerman J M, Fujisawa T, Tarucha S and Kouwenhoven L P 2003 Rev. Mod. Phys. 75 1 [3] Hanson R, Kouwenhoven L P, Petta J R, Tarucha S and Vandersypen L M K 2007 Rev. Mod. Phys. 79 1217 [4] Galpin M R et al 2006 J. Phys.: Condens. Matter 18 6571 [5] Hofstetter W, König J and Scheller H 2001 Phys. Rev. Lett. 87 156803 [6] Tanaka Y and Kawakami N 2004 J. Phys. Soc. Jpn. 73 2795 Tanaka Y and Kawakami N 2005 Phys. Rev. B 72 {085304} [7] Yan C H, Wu S Q, Huang R and Sun W L 2006 Chin. Phys. Lett. 23 1888 Yang F B, Wu S Q and Sun W L 2007 Chin. Phys. Lett. 24 {2056} [8] Huang R, Wu S Q, Yan C H and Sun W L 2006 Chin. Phys. Lett. 23 1892 Chi F and Li S S 2005 Chin. Phys. Lett. 22 {2035} [9] Tomosuke A and Mikio E 2001 Phys. Rev. B 63 125327 [10] Pohjola T, König J, Salomaa M M, Schmid J, Schoeller H and Schön G 1997 Europhys. Lett. 40 189 [11] Hewson A C 1993 The Kondo Problem to Heavy Fermions (Cambridge: Cambridge University) Coleman P 1984 Phys. Rev. B 29{3035} [12] Wu S Q and Wang S J 2003 Chin. Phys. Lett. 20 1574 Chen X W et al 2004 Chin. Phys. Lett. 21 {911} [13] Rui S and Norio K 2005 Phys. Rev. B 72 085303 [14] Borda L, Zarand G, Hofstetter W, Halperin B I and Von Delft J 2003 Phys. Rev. Lett. 90 026602 [15] Wilhelm U and Weis J 2000 Physica E 6 668 Sun Q F and Guo H 2002 Phys. Rev. B 66