1202.2040 (S. Pfalz et al.)

Electron spin orientation under in-plane optical excitation in GaAs
quantum wells    [PDF]

S. Pfalz, R. Winkler, N. Ubbelohde, D. Hägele, M. Oestreich

We study the optical orientation of electron spins in GaAs/AlGaAs quantum
wells for excitation in growth direction and for in-plane excitation. The time
and polarization resolved photoluminescence excitation measurements show for
resonant excitation of the heavy-hole conduction band transition a negligible
degree of electron spin polarization for in-plane excitation and nearly 100%
for excitation in growth direction. For resonant excitation of the light-hole
conduction band transition, the excited electron spin polarization has for
in-plane excitation (in growth direction) excitation the same (opposite)
direction as for excitation into the continuum. The experimental results are
well explained by an accurate multiband theory of excitonic absorption taking
fully into account electron-hole Coulomb correlations and heavy-hole light-hole
coupling.

View original: http://arxiv.org/abs/1202.2040