Generation of spin-polarized current using multiterminal quantum dot with spin-orbit interaction

Tomohiro Yokoyama, Mikio Eto

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We theoretically examine generation of spin-polarized current using multiterminal quantum dot with spin-orbit interaction. First, a two-level quantum dot is analyzed as a minimal model, which is connected to N (2) external leads via tunnel barriers. When an unpolarized current is injected to the quantum dot from a lead, a polarized current is ejected to others, similarly to the spin Hall effect. In the absence of magnetic field, the generation of spin-polarized current requires N3. The polarization is markedly enhanced by resonant tunneling when the level spacing in the quantum dot is smaller than the level broadening due to the tunnel coupling to the leads. In a weak magnetic field, the orbital magnetization creates a spin-polarized current even in the two-terminal geometry (N=2). The numerical study for generalized situations confirms our analytical result using the two-level model.

Original languageEnglish
Article number205305
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume86
Issue number20
DOIs
Publication statusPublished - 2012 Nov 6

Fingerprint

spin-orbit interactions
Semiconductor quantum dots
Orbits
quantum dots
Tunnels
Spin Hall effect
tunnels
Magnetic fields
Resonant tunneling
resonant tunneling
Magnetization
magnetic fields
Lead
Hall effect
Polarization
spacing
Geometry
orbitals
magnetization
polarization

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Generation of spin-polarized current using multiterminal quantum dot with spin-orbit interaction. / Yokoyama, Tomohiro; Eto, Mikio.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 86, No. 20, 205305, 06.11.2012.

Research output: Contribution to journalArticle

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