Spin Dynamics in Double Quantum Dots in the Spin Blockade Regime Articles uri icon

publication date

  • January 2010

start page

  • 643

end page

  • 648

issue

  • 3

volume

  • 42

International Standard Serial Number (ISSN)

  • 1386-9477

Electronic International Standard Serial Number (EISSN)

  • 1873-1759

abstract

  • We analyze theoretically the effect of dynamical nuclear spin polarization on the electronic transport through a double quantum dot in the spin blockade (SB) regime in the presence of hyperfine interaction.
    The electron and nuclei hyperfine interaction produces electron spin
    flip which partially removes SB. Induced nuclei spin polarization
    produces a finite magnetic field which acts on the electrons generating
    an additional Zeeman splitting of the electronic spin up and down levels
    in each quantum dot. This additional Zeeman splitting changes
    dynamically with the electronic level occupation. Then, strong feedback
    between the induced nuclear polarization within each quantum dot and the
    electronic charge distribution occurs and it produces strong
    non-linearities in the current as a function of both, external magnetic
    field and dc voltage. We analyze as well electron spin resonance in a
    double quantum dot driven by crossed dc and ac magnetic fields. The time
    dependent magnetic field produces coherent electron spin rotations
    within each quantum dot. In this configuration, spatial Rabi
    oscillations due to inter-dot tunnel compete with Rabi oscillations
    between spin up and down states induced by the time dependent magnetic
    field, giving rise to a complicated time dependent behavior of the
    tunneling current.