Gate-induced g-factor control and dimensional transition for donors in multivalley semiconductors

Rajib Rahman, Purdue University - Main Campus
Seung H. Park, Purdue University - Main Campus
Timothy B. Boykin, University of Alabama - Huntsville
Gerhard Klimeck, Network for Computational Nanotechnology, Purdue University
Sven Rogge, Delft Univ Technol, Kavli Inst Nanosci
Lloyd CL Hollenberg, Univ Melbourne, Sch Phys, Ctr Quantum Comp Technol

Abstract

The dependence of the g factors of semiconductor donors on applied electric and magnetic fields is of immense importance in spin-based quantum computation and in semiconductor spintronics. The donor g-factor Stark shift is sensitive to the orientation of the electric and magnetic fields and is strongly influenced by the band-structure and spin-orbit interactions of the host. Using a multimillion atom tight-binding framework, the spin-orbit Stark parameters are computed for donors in multivalley semiconductors, silicon, and germanium. Comparison with limited experimental data shows good agreement for a donor in silicon. Results for gate-induced transition from three-dimensional to two-dimensional wave-function confinement show that the corresponding g-factor shift in Si is experimentally observable, and at modest B field, O(1 T) can exceed the Stark shift of the hyperfine interaction.

Discipline(s)

Engineering | Nanoscience and Nanotechnology