COHERENT OPTICAL POLARIZATION OF BULK GAAS STUDIED BY FEMTOSECOND PHOTON-ECHO SPECTROSCOPY

Authors
LOHNER A RICK K LEISCHING P LEITENSTORFER A ELSAESSER T KUHN T ROSSI F STOLZ W
Citation
A. Lohner et al., COHERENT OPTICAL POLARIZATION OF BULK GAAS STUDIED BY FEMTOSECOND PHOTON-ECHO SPECTROSCOPY, Physical review letters, 71(1), 1993, pp. 77-80
Citations number
20
Categorie Soggetti
Physics
Journal title
Physical review letters → ACNP
ISSN journal
00319007
Volume
71
Issue
1
Year of publication
1993
Pages
77 - 80
Database
ISI
SICI code
0031-9007(1993)71:1<77:COPOBG>2.0.ZU;2-X
Abstract
The nonlinear polarization close to the band gap of GaAs is studied by spectrally and temporally resolved four-wave mixing. Excitonic and fr ee carrier contributions both excited within the bandwidth of the 100 fs pulses are distinguished for the first time. The excitonic part dom inates at carrier densities below 10(16) cm-3. At higher density, nont hermalized free carriers give rise to an additional component resonant to the pulse that shows a photon-echo-like time behavior. Monte Carlo simulations including the coherent polarization and the scattering dy namics of the carriers account for the data.