Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 53: Optical properties

HL 53.5: Vortrag

Freitag, 29. Februar 2008, 11:30–11:45, EW 201

Carrier spin dynamics in GaAs/AlGaAs quantum wells, studied by time-resolved Kerr rotation — •Liudmila Fokina, Dmitri Yakovlev, and Manfred Bayer — TU Dortmund,Experimentelle Physik II,D-44221 Dortmund

We study of the electron spin coherence in GaAs/AlGaAs quantum wells heterostructures with a low-dense as well high dense two dimensional electron gas with help of the pump-probe time-resolved Kerr rotation technique. To explore the spin relaxation mechanism, we performed a systematic study of the dependence of the spin dephasing time on the characteristic parameters as temperature, magnetic field and electron concentration. Electron spin beats have been measured in magnetic field, which a precession frequency allows to determine the transverse component of the electron g-factor. When the spin dephasing times becomes longer than several ns, we used the technique of the resonant spin amplification (RSA), which has been developed to extract spin lifetimes that exceed the pulse repetition interval. We describe an interesting behaviour of the RSA signal in the interval of zero magnetic field.