Theoretical Study on Spin Polarization of III-V Compound Tips

Abstract

We investigate spin electronic structures of GaN probes, using first principles molecular orbital calculations. It is found that at the pyramidal heads of the probes with the axes parallel to the crystallographic axes [100] and [111] in the zincblende GaN, electron spins are polarized at the lowest energy states. Nearly 8%∼16% of electrons in the valence band are spin-polarized at the proximity of the head depending upon the sort of the atom on the apex and the crystallographic axis of the probe. It is observed that spin polarizability depends on the difference of electronegativities of the elements in a compound and on a highly symmetric nanostructure of the probe. It is due to Jahn-Teller effect of the tip configuration.