Spin-orbit Interaction and Energy States in Nanoscale Semiconductor Quantum Rings

Y. Li
Natl Nano Device Labs & Natl Chiao Tung Univ, TW

Keywords: spin-orbit splitting, energy states, InAs/GaAs, quantum ring, quantum dot

Abstract:
We investigate the effect of spin-orbit interaction on the electron energy states in nanoscale semiconductor quantum rings. The effective one-band Hamiltonian approximation with the spin-dependent Ben Daniel-Duke boundary conditions is formulated and solved numerically. Due to significant spin-orbit interaction in the nonsimply connected torus topology, experimentally measurable spin splitting can be observed in InAs/GaAs quantum ring. The spin splitting depends on the variations of geometric (dot- and ring-liked) structures. They are dominated by the inner radius, base radius, and height of the quantum ring. Under zero magnetic fields, it is found that quantum ring can produce ~ 2 meV spin splitting of excited electronic states which is substantially larger than that of quantum dot (~ 1meV).

Nanotech 2004 Conference Technical Program Abstract