-
[show abstract]
[hide abstract]
ABSTRACT: Three-dimensional anisotropy of the Lande g-factor and its electrical
modulation are studied for single uncapped InAs self-assembled quantum dots
(QDs). The g-factor is evaluated from measurement of inelastic cotunneling via
Zeeman substates in the QD for various magnetic field directions. We find that
the value and anisotropy of the g-factor depends on the type of orbital state
which arises from the three-dimensional confinement anisotropy of the QD
potential. Furthermore, the g-factor and its anisotropy are electrically tuned
by a side-gate which modulates the confining potential.
03/2013;
-
Physical Review B 01/2011; 84:041302. · 3.69 Impact Factor
-
AIP Conference Proceedings 01/2011; 1399:355.
-
Nature Nanotechnology 01/2011; 7(1):75. · 27.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Electrical control over electron spin is a prerequisite for spintronics spin-based quantum information processing. In particular, control over the interaction between the orbital motion and the spin state of electrons would be valuable, because this interaction influences spin relaxation and dephasing. Electric fields have been used to tune the strength of the spin-orbit interaction in two-dimensional electron gases, but not, so far, in quantum dots. Here, we demonstrate that electrical gating can be used to vary the energy of the spin-orbit interaction in the range 50-150 µeV while maintaining the electron occupation of a single self-assembled InAs quantum dot. We determine the spin-orbit interaction energy by observing the splitting of Kondo effect features at high magnetic fields.
Nature Nanotechnology 01/2011; 6(8):511-6. · 27.27 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The anisotropy of the spin-orbit interaction (SOI) is studied for a single uncapped InAs self-assembled quantum dot holding just a few electrons. The SOI energy is evaluated from anticrossing or SOI-induced hybridization between the ground and excited states with opposite spins. The magnetic angular dependence of the SOI energy falls on an absolute cosine function for azimuthal rotation, and a cosinelike function for tilting rotation. Furthermore, the SOI energy is quenched for a specific magnetic field vector. The angular dependence of SOI is found to compare well with calculation of Rashba SOI in a two-dimensional harmonic potential.
Physical Review Letters 06/2010; 104(24):246801. · 7.37 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Anisotropy of spin-orbit interaction (SOI) is studied for a single uncapped
InAs self-assembled quantum dot (SAQD) holding just a few electrons. The SOI
energy is evaluated from anti-crossing or SOI induced hybridization between the
ground and excited states with opposite spins. The magnetic angular dependence
of the SOI energy falls on an absolute cosine function for azimuthal rotation,
and a cosine-like function for tilting rotation. The SOI energy is even
quenched at a specific rotation. These angular dependence compare well to
calculation of Rashba SOI in a two-dimensional harmonic potential.
12/2009;
