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RESEARCH PRODUCT

Excitons in SiO2: a review

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Abstract In this paper, excitonic properties of crystalline and glassy SiO 2 are reviewed. Experimental spectroscopic data (optical absorption and reflection spectra, as well as spectra of luminescence and its excitation), luminescence decay kinetics at different temperatures, and photoelectric properties — photoconductivity and photoelectron emission — were used to determine excitons in SiO 2 . Information on migration of excitons was obtained on the basis of energy transport to impurity luminescence centers, the latter being detectors of quasiparticles. Determination of excitonic properties in glassy SiO 2 was based on the comparison of the observed phenomena in crystalline and glassy materials in approximately the same conditions. Structural peculiarities are analyzed comparing optical phenomena in crystalline α-quartz and cristobalite and in fused silica of four types. Models of excitons are based on propositions of chemical bond theory and total energy adiabatic potential.