  The studies of spin phenomena in semiconductor low dimensional systems have
grown into the rapidly developing area of the condensed matter physics:
spintronics. The most urgent problems in this area, both fundamental and
applied, are the creation of charge carrier spin polarization and its detection
as well as electron spin control by nonmagnetic methods. Here we present a
review of recent achievements in the studies of spin dynamics of electrons,
holes and their complexes in the pump-probe method. The microscopic mechanisms
of spin orientation of charge carriers and their complexes by short circularly
polarized optical pulses and the formation processes of the spin signals of
Faraday and Kerr rotation of the probe pulse polarization plane as well as
induced ellipticity are discussed. A special attention is paid to the
comparison of theoretical concepts with experimental data obtained on the
n-type quantum well and quantum dot array samples.
