Specific features of the telluride glasses doped by Pr3+ nanocrystallites

Photoinduced two-photon absorption (TPA) measurements of Pr3+-doped Te glasses under illumination of excimer Xe–F laser (λ = 221 nm) (as a source of the photoinducing pumping beam) was performed. The pumping beam formed a thin surface layer in which photoinduced TPA was observed. The Raman shifted Nd–YAG laser radiation (λ = 2.9 μm) as well as its second and fourth harmonics (λ = 1450 and 725 nm, respectively) were used as probing beams. The highest values of the TPA β-coefficient were obtained for the parallel polarizations between the pumping and probing beams. The obtained values of TPA coefficients indicate a possibility of using Pr3+-doped nanocrystals incorporated into glasses as optically-operated limiters in the wide spectral range. Higher output TPA was achieved for collinear pump-probe light polarization. Substantial role of anharmonic electron–phonon subsystem is demonstrated.