Singlet-triplet avoided crossings and effectivegfactor versus spatial orientation of spin-orbit-coupled quantum dots

2010/09/28 by M. P. Nowak, B. Szafran
Mathematics · Physics and Astronomy · #Anisotropy #Atomic physics #Condensed matter physics #Coupling (piping) #Excited state #Field (mathematics) #Geometry #Magnetic field #Magnetic properties of thin films #Materials science #Mathematics #Orientation (vector space) #Perpendicular #Physics #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Semiconductor Quantum Structures and Devices #Singlet state #Spectral line #Spin (aerodynamics) #Spins #Spin–orbit interaction #Zeeman effect #cond-mat.mes-hall

paper · pdf · doi:10.1103/physrevb.83.035315

published as M. P. Nowak and B. Szafran, Phys. Rev. B 83, 035315 (2011)

arxiv created 2010/09/28 · openalex publication_date 2011/01/19 · arxiv updated 2013/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We study avoided crossings opened by spin-orbit interaction in the energy spectra of one- and two-electron anisotropic quantum dots in perpendicular magnetic field. We find that for simultaneously present Rashba and Dresselhaus interactions the width of avoided crossings and the effective g factor depend on the dot orientation within the (001) crystal plane. The extreme values of these quantities are obtained for [110] and [110] orientations of the dot. The width of singlet-triplet avoided crossing changes between these two orientations by as much as two orders of magnitude. The discussed modulation results from the orientation-dependent strength of the Zeeman interaction, which tends to polarize the spins in the direction of the external magnetic field and thus remove the spin-orbit coupling effects.

Citations

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