Impurities

Objective:

• Study Stark Shift of the g-factor for an isolated donor w.r.t. expt in Si and Ge.
• g-factor shift for interface-donor system.
• Probes spin-orbit effects with electric fields and symmetry change.
• Effect of relative orientations of B and E field.

Approach:

• The 20 band nearest neighbor sp3d5s* spin model captures SO interaction of the host.
• Same atom p orbital energy between spin orbitals.
• g-factor obtained from orbital and spin angular momentum operators.
• Donor wfs with E-field are obtained from NEMO

Results / Impact:

• Quadratic Stark coefficient from TB agrees with measured value in magnitude.
• Relative E and B orientations seem to affect g-factor shift. Linear effect for shallow donors.
• Understanding of the B field dynamics of the donor electron.