Light Propagation and Disorder Effects in Semiconductor Multiple Quantum Wells

Propagation of femtosecond light pulses in semiconductor multiple quantum wells with interface roughness is investigated theoretically and experimentally. It is shown that the nonlocal susceptibility causes exciton broadening, decreases the relative magnitude of the 1s and 2s resonances, and leads to multiple reflections. The time resolved signal exhibits modulations that are sensitive to the barrier thickness. The absorption spectrum and time dependence of the beat frequency are influenced by static disorder.