title: Spin-orbit induced electronic spin separation in semiconductor nanostructures.
abstract: The demonstration of quantized spin splitting by Stern and Gerlach is one of the most important experiments in modern physics. Their discovery was the precursor of recent developments in spin-based technologies. Although electrical spin separation of charged particles is fundamental in spintronics, in non-uniform magnetic fields it has been difficult to separate the spin states of charged particles due to the Lorentz force, as well as to the insufficient and uncontrollable field gradients. Here we demonstrate electronic spin separation in a semiconductor nanostructure. To avoid the Lorentz force, which is inevitably induced when an external magnetic field is applied, we utilized the effective non-uniform magnetic field which originates from the Rashba spin-orbit interaction in an InGaAs-based heterostructure. Using a Stern-Gerlach-inspired mechanism, together with a quantum point contact, we obtained field gradients of 10(8) T m(-1) resulting in a highly polarized spin current.
authors.affiliation: Department of Materials Science, Tohoku University, 6-6-02 Aramaki-Aza Aoba, Aoba-ku, Sendai 980-8579, Japan. makoto@material.tohoku.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Kohda
authors.forename: Shuji
authors.initials: S
authors.lastname: Nakamura
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Nishihara
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Teruo
authors.initials: T
authors.lastname: Ono
authors.forename: Jun-ichiro
authors.initials: J
authors.lastname: Ohe
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tokura
authors.forename: Taiki
authors.initials: T
authors.lastname: Mineno
authors.forename: Junsaku
authors.initials: J
authors.lastname: Nitta
mesh_terms: D004581:Electronics; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology; D012666:Semiconductors