It has been shown recently that heating of cold holes can be studied selectively in direct gap semiconductors with use of a femtosecond two-color absorption saturation technique. Cold-carrier heating investigation is particularly interesting because the efficiency of phonon absorption is proportional to their occupation number; carrier-phonon energy transfer is strongly dependent on the lattice temperature (in contrast to carrier cooling) and can thus be separated from other scattering processes. This study exploits this temperature dependence to study hole-optical phonon interactions in bulk GaAs. The measurements take advantage of the fact that the k-space spreading of a thermal hole distribution is much larger than the electron one.
Ultrafast hole-phonon interactions in GaAs
Tommasi R.;
1996-01-01
Abstract
It has been shown recently that heating of cold holes can be studied selectively in direct gap semiconductors with use of a femtosecond two-color absorption saturation technique. Cold-carrier heating investigation is particularly interesting because the efficiency of phonon absorption is proportional to their occupation number; carrier-phonon energy transfer is strongly dependent on the lattice temperature (in contrast to carrier cooling) and can thus be separated from other scattering processes. This study exploits this temperature dependence to study hole-optical phonon interactions in bulk GaAs. The measurements take advantage of the fact that the k-space spreading of a thermal hole distribution is much larger than the electron one.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
