In the second part of my talk\, I investigate the geometric phase induced on the spin states during the adiabatic movement of the III-V semiconductor quantum dots in the plane of two-dimensional electron gas under the influence of applied gate potential along the lateral direction. Here\, I present the spin-flip probabilities during the adiabatic evolution in the presence of the Rashba and the Dresselhaus linear spin-orbit interactions. I use the Feynman disentanglement technique to determine the non-Abelian Berry phase and find exact analytical expressions for three special cases: (a) the pure Rashba spin-orbit coupling\, (b) the pure Dresselhause linear spin-orbit coupling\, and (c) the mixture of the Rashba and Dresselhaus spin-orbit couplings with equal strength. For a mixture of the Rashba and the Dresselhaus spin-orbit couplings with unequal strengths\, I obtain numerical results by solving the Riccati equation originating from the disentangling procedure. I find that the spin-flip probability in the presence of the mixed spin-orbit couplings is generally larger than those for the pure Rashba case and for the pure Dresselhaus case\, and that the complete spin-flip takes place only when the Rashba and the Dresselhaus spin-orbit couplings are mixed symmetrically.

References:

Gate control of a quantum dot single-electron spin in realistic confining potentials: Anisotropy effects; Sanjay Prabhakar and James Raynolds\, phys. Rev. B 79\, 195307 (2009).

Manipulation of single electron spin in a GaAs quantum dot through the application of geometric phases: The Feynman disentangling technique; Sanjay Prabhakar\, James E Raynolds\, Akira Inomata and Roderick Melnik\, Phys. Rev. B 82\, 195306 (2010).

Manipulation of the Lande g-factor in InAs quantum dots through the application of anisotropic gate potentials; Sanjay Prabhakar\, James E Raynolds and Roderick Melnik\, Phys. Rev. B 84\, 155208 (2011).

The influence of anisotropic gate potentials on the phonon induced spin-flip rate in GaAs quantum dots; Sanjay Prabhakar\, Roderick Melnik and Luis L Bonilla\, Applied Physics Letters 100\, 023108 (2012).

URL:http://www.physics.wisc.edu/twap/view.php?id=2972 END:VEVENT END:VCALENDAR