OBSERVATION OF OPTICAL STARK EFFECT OF CONTINUUM STATES IN CdS

F. Henneberger, J. Puls, H. ROSSMANN

I. Cojocari, Valentin N. Ciumash, I. I. Dobinda +2 more

I. Broser, J. Gutowski

Nasser N. Peyghambarian, Stephan W. Koch, Markus Lindberg +2 more

The first observation of the optical Stark effect of electron-hole continuum states in addition to the bound-exciton states is reported under femtosecond excitation conditions chosen to minimize the generation of real carriers. The experimental results agree well with calculations using the generalized semiconductor Bloch equations. The theory shows that the commonly used adiabatic approximation is correct only for pulses which are longer than the coherence decay time. For shorter pulses coherent dynamic effects strongly influence the spectral changes.

Nguyễn Hồng Quang

Optical Stark effect of the exciton in quantum wells is treated by taking into account not only dynamical coupling by pump field between quantized states of the electron in the conduction band but also the coupling between quantized states of the hole in the valence band. The changes in the calculated one-photon absorption probability by exciton depend essentially on pump field detuning.

F. Henneberger, J. Puls, H. Rossmann