title: Kondo effect in a semiconductor quantum dot with a spin-accumulated lead.
abstract: We study the Kondo effect in a semiconductor quantum dot in contact with a spin-accumulated lead. The spin accmulation in a nonmagnetic semiconductor is realized by spin injection from a spin-polarized quantum point contact in combination with magnetic focusing, thus creating spin-unbalanced chemical potentials. We demonstrate that the spin splitting of the Kondo densities of states (DOS) for spin-up and spin-down electrons can be controlled by selectively shifting only the spin-up DOS using spin accumulation. We also show the possibility to recover the Kondo effect in a high magnetic field, by compensating for Zeeman splitting by spin accumulation.
authors.affiliation: NTT Basic Research Laboratories, Atsugi-shi, Kanagawa 243-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: S
authors.initials: S
authors.lastname: Tsuruta
authors.forename: S
authors.initials: S
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Fujisawa
authors.forename: Y
authors.initials: Y
authors.lastname: Tokura
authors.forename: T
authors.initials: T
authors.lastname: Akazaki