Abstract

In last years two-photon absorption (TPA) spectroscopy has been demonstrated ^[1] to be a powerful tool to investigate the excitonic states of confined systems providing complementary information with respect to the one obtained by linear techniques. In this paper we report TPA experimental measurements performed at T=10K on semiconductor-doped glasses, containing CdS_1-xSe_x particles of various average size but having the same selenium concentration. Linear absorption (ABS) measurements and photoluminescence excitation induced by one- and two-photon absorption (OPA-PLE, TPA-PLE) techniques are employed. The laser source is a two-stage amplified dye laser pumped by the second and third harmonic of a Nd: YAG laser, operating at 10 Hz and with 9 nsec pulse width, and equipped with a low pressure H₂ Raman-shifter.

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