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We embedded CdSe nanocrstallites into a porous glass with a diffusion process. Using picosecond time resolved luminescence spectrum technique, we investigated the electron dynamics in the CdSe microcrystallites in porous glass. The luminescence decay of our sample has a fast component decay sensitive to temperature. For a sample of CdSe microcrystallites with an average size of 25 Å diameter, the fast decay is 50 ps at 77 K, and is 100 ps at 2 K. With a simple three level model, the luminescence decay is simulated. The temperature dependence of luminescence decay results from nonradiative process.

The nonlinear optical properties of CdTe microcrystallites embedded in CaF2 by pulsed laser beam and electron beam coevaporation method are investigated with pump-probe technique. Only bleaching effect around wavelength region corresponding to the larger size microcrystallites can be obtained. The bleaching spectra are simulated with a state filling model. The upper energy states of the quantum confinement microcrystallites are perhaps also important to the nonlinear optical properties of microcrystallites.

Based on previous results, we calculate the ground state energy, the first excited state energy, and the binding energy of an exciton in a polar crystal slab. We find that the polaron effect increases the binding energy of the slab exciton, but decreases the energy difference between the first excited state energy and the ground state energy. [Russian Text Ignored].

The authors use the method suggested by Huybrechts (1978) to study a bound polaron in a three-dimensional polar crystal. They assume the walls of the quantum well to be infinitely high and choose the variational wavefunction to be that used by Bastard (1981) in a study of the states of shallow donors in a quantum well. They investigate the effect of the interaction of electrons with phonons (the phonons include bulk longitudinal optical phonons and surface optical phonons) on the binding energy of shallow donors confined in a quantum well. They find that the effect of polarons increases the binding energy of shallow donors. For the GaAs-Ga1-xAlxAs quantum well, when the L/a0 ratio (where L is the width and a0 the effective Bohr radius) is decreased from 4 to 1, the binding energy increases from 0.3 to 1.3 meV.

In this paper, a weak-coupling exciton-phonon system in a polar-crystal slab is studied. A unitary transformation to the Hamiltonian is carried out, the effective Hamiltonian of the exciton-phonon system is obtained by variational technique. The variation of the self-energy and the induced potential with the thickness of the slab is calculated. Eventually, the ground-state and the first-excited-state energy of the exciton in the slab for different thicknesses of the slab are calculated by the variational method.