The nonlinear propagation of picosecond pulses in CdTe is investigated. First, the band‐gap dynamics is studied in the presence of a dense electron‐hole plasma using time‐resolved luminescence in the picosecond regime. Good agreement is found between experimental results for band‐gap shrinkage and theory for densities of 5×1016–4×1017cm−3. Second, the nonlinear transmission of optical pulses through CdTe/CdZn0.04Te0.96heterostructures is investigated for photon energies close to the unexcited band gap. We demonstrate that, depending on the energy of the incident pulse, induced transmission or induced absorption takes place: Self‐induced transmission is caused by band filling at high intensityEof the incident pulses (Ebartil;100–200 mgr;J/cm2). Self‐induced absorption is observed at relatively low incident intensity (Ebartil;15–20 mgr;J/cm2). This effect is related to the band‐gap shrinkage of the CdTe epilayer in the presence of a nondegenerate electron‐hole plasma. A transmission theory of picosecond pulses propagating in and exciting the sample simultaneously is developed and provides a qualitative description of the experimental data.
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