Spin–orbit coupling and -factor of -valley in cubic GaN

Abstract

We report our theoretically investigation on the spin-orbit coupling and g-factor of the X-valley in cubic GaN. We find that the spin-orbit coupling coefficient from sp 3 d 5 s * tight-binding model is 0.029 eV·Å, which is comparable with that in cubic GaAs. By employing the k · p theory, we find that the g-factor in this case is only slightly different from the free electron g-factor. These results are expected to be important for the on-going study on spin dynamics far away from equilibrium in cubic GaN.PACS numbers: 71.70. Ej, 61.82.Fk Due to the existence of the wide energy gap between the conduction band and the valence band, GaN has been proposed to be a promising candidate for many electronic applications, such as the solid-state ultraviolet optical sources and high-power electronic devices.

Strain dependent electron spin dynamics in bulk cubic GaN

“…For a quantitative comparison of the experimental spin relaxation rate and its strain dependence to the predictions of DP theory, the spin splitting constant c e , the strain spin splitting constant C 3 and the momentum scattering times s i p have to be known. The spin splitting constant c e in c-GaN has only been theoretically predicted by few tight-binding calculations, 26,[55][56][57] resulting in values between c e ¼ 0.235 eV Å 3 and c e ¼ 0.84 eV Å 3 , while no experimental values are available. As the strain spin splitting constant C 3 is not known for c-GaN, we estimate its value via expressions derived within k Á p-theory, 20,25,49,58 giving in lowest order…”