IJM01 Spin-orbit splitting dependent single-colour multiphoton absorption spectroscopy and spin orientation in noncentrosymmetric semiconductors with narrow to wide bandgaps

Abstract

We study the spin-orbit splitting dependent single-coloured multiphoton absorption spectroscopy and spin orientation in noncentrosymmetric InSb, GaSb and ZnSe by calculations of spectra for these compounds. Calculations are focused on the photon-frequency dependent absorption and spin generation on the basis of the Kane model. It is found that the electronic spin polarization (P) depends on the absorption scheme of the spectroscopy as well as pumping direction and excess photon energy of exciting carriers. A maximum value of P is found to be about 55%. The P reaches its maximum value at the lower energy and sustains shorter energy range for InSb. The P is also found to depend on the bandgap energy and spin-orbit splitting. The results show that due to a much longer absorption depth multiphoton absorption enhances the spin generation and thus spin polarization.