J.B. Grun

Two-photon absorption in CuCl

Abstract The two-photon absorption spectrum of CuCl at 4.2°K is studied in the energy range of the excitonic lines. The observed lines are suggested to be due to the creation of excitons in the 1S, 2P and 3P states and also to the simultaneous creation of 2P and 3P excitons and one or more longitudinal optical phonons.

Two-photon absorption in CuBr

Abstract The two-photon absorption constant is measured in the exciton region of CuBr. Three exciton lines are observed and interpreted as due to a 1S longitudinal exciton, a 2P exciton and its LO phonon side band. The spectrum is explained by Mahans two-band model.

Intensity dependence of emission lines in CdS upon excitation intensity (laser) at very low temperature

Abstract The dependence of the emission intensity upon excitation intensity (laser) is reported for free exciton recombination (A 1 ) and for phonon-assisted free exciton recombination (A 1 -LO) in CdS at 4.2°K. For an excitation intensity threshold, A 1 becomes sublinear, A 1 -LO superlinear.

Excitonic absorption and emission of cuprous chloride during excitation by a powerful light source

Abstract The excitonic absorption line of CuCl is shifted towards higher energies when the sample is excited by a powerful light source; on the contrary, the emission line is not shifted. Several explanations of these observations are given.

High concentrations of carriers and excitons in copper halides crystals

Abstract Large concentrations of carriers and excitons are created by laser excitation in copper halides crystals at low temperatures. A drastic change of the absorption spectrum of these samples has been observed: decrease and shift of the excitonic lines.

Luminescence of CuCl at low temperatures excited by very high intensity light (laser)

Abstract The luminescence of CuCl excited by double photon absorption (laser) is compared to single photon excitation with conventional and high intensity light. The spectra obtained are different in every case. Repetitive laser shots modify permanently the emission spectrum of CuCl.

Structure oscillatoire dans le spectre de photoconductive de CuCl

Abstract La courbe de reponse photoelectrique dechantillons exceptionnels du CuCl presente, a 4°K, une structure vibratoire. Le nombre donde 216 cm −1 trouve est voisin du phonon optique longitudinal. Les maxima correspondent aux minima de la courbe dabsorption observee precedemment.