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We report measurements of dynamic (a.c.) electrical conductivity in borosilicate glasses doped with cadmium sulfoselenide and copper and silver iodides in a wide temperature range below the glass transition temperature T g and at different frequencies. The concentration of the mobile dopant ions is governed by specific heat treatment conditions of the glass samples leading to a creation of the CdSSe, AgI and CuI semiconductor nanocrystals. Investigations include different cases from a full solution of the dopant ions coming from a dissociation of the dopants during the glass preparation to their almost complete incorporation into the nanocrystals in the glass matrix. At temperatures higher than 150 °C–200 °C the a.c. conductivity in all the examined glasses exhibits the Arrhenius behavior. In this temperature range the mixed mobile ion effect is detected: the doped glasses have the low values of the conductivity compared to the undoped ones. In the low temperature range only weak temperature dependence is detected for all the samples. The mixed mobile ion effect is still presented for the CdSSe-doped glasses, whereas the AgI- and CuI-doped glasses exhibit the classical MMIE which is essentially absent at low temperatures.

The absorption spectra of CuBr, CuCl, CuI, and AgI nanocrystals (NC) embedded in a glass matrix have been investigated in a wide temperature range between T =6 and 860 K. The change of the absorption in the vicinity of the exciton resonance for CuBr and CuCl reveals a pronounced reduction of the melting temperature of NCs compared to the bulk value and shows a strong hysteresis between melting and solidification temperatures. The melting temperature and the hysteresis width depend on the sizes of NCs. For CuBr NCs a second hysteresis around the bulk melting point is observed. For large NCs the temperature dependence of the exciton peak energies is analogous to its counterpart in bulk crystals. For CuI NCs the shrinkage effect of the gap for both cubic and hexagonal modifications is observed and the temperature coefficients of the energy gaps are deduced. For AgI NCs a rather unusual temperature dependence of energy gap is observed. This dependence is nonmonotonic and shows a change of the energy gap slope from positive to negative.

The results on the selective photoluminescence (PL), photoluminescence excitation (PLE) and the degree of linear polarization (DLP) for the PL spectrum in AgI nanocrystals (NC) embedded in a glass host matrix are presented. The measurements indicate a fine structure of the exciton ground state due to the electron–hole exchange interaction: the PL originates from the lowest triplet state (“dark” exciton) when the higher singlet state (“bright” exciton) is excited. The obtained negative DLP confirms that the emitting state is not directly excited by the pump light, but is created through the virtual interaction with a higher excitonic state of different polarization features and subsequent relaxation. The corresponding red shift of the PL spectrum with respect to the PLE spectrum has been studied in dependence on the NC size. The exchange splitting shows a pronounced size dependence strongly increasing with a restriction of the dot radii. The value of the exchange energy of the exciton for AgI bulk crystals is determined. Both the short- and long-range contributions to the exchange splitting are discussed.

The temperature dependence of exciton peak energies in large CuI quantum dots embedded in a glass matrix has been measured. The gap shrinkage effect for both cubic and hexagonal CuI phases was observed. The temperature coefficients of the energy gaps and the effective phonon energies are deduced.

An investigation was made of the kinetics of lasing in neodymium-doped silicate glasses in the form of thin needle-shaped rods with diameters ~ 1 mm and 30–40 cm long. A similarity with fiber lasers was observed. The output radiation included regular giant pulses, which appeared because of bleaching of short-lived color centers. Quasi-cw lasing with relaxation-type oscillations and mode self-locking, accompanied by the emission of a series of ultrashort laser pulses, was observed.

A description is given of a composite waveguide structure, containing a polystyrene film with added methyl-red dye as the active medium. A reversible optical induced change in the waveguide light intensity was discovered. The temporal characteristics of the photochemical process were investigated. The possibilities for using such waveguides in integrated optics are indicated.

A study was made of the action of high power laser pulses on the surface of an optical waveguide. It was established that the threshold for surface damage is mainly dependent on the laser pulse parameters and on the condition of the surface. A yellow coloration was found to appear in the irradiated zone. A mechanism is proposed for the formation of colloidal silver particles, which are responsible for the coloration.