Glass formation and the third harmonic generation of Cu2Se–GeSe2–As2Se3 glasses

Abstract

We have performed the investigation of the nonlinear optical properties namely the third harmonic generation (THG) of the glass-formation region in the Cu2Se–GeSe2–As2Se3 system. The samples were synthesized by direct single-temperature method from high-purity elementary substances. We have found that the value of disorder parameter Δ depends on the composition of the glassy alloys. The measurements show that increasing the Cu2Se concentration leads to increased slope of the absorption edge, which may be explained by the decrease of the height of random potential relief for the electrons in the tails of the state density which border the band edges. A very sharp increase in the THG at low temperature was observed. Significant enhancement in THG was obtained with decreasing the energy gap, which agreed well with the nonlinear optical susceptibilities obtained from other glasses.

Spherulitic crystallization of quartz-like GeO2 and correlated second harmonic generation in sodium tantalum germanate glasses

“…On the other hand, welldesigned glass compositions, usually doped with rare earth active ions, are also able to emit specific wavelengths of technological interest and are applied for optical amplification or glass-based laser cavities [10][11][12]. Other research field of great interest is related with the non-linear interaction of light with glassy materials, giving rise to non-linear optical responses such as multiphoton absorption or non-linear refractive index [13], [14]. Besides these third order non-linear properties, preliminary suitable treatments of the mother glass can break the glass isotropy and second order non-linear effects such as Second Harmonic Generation (SHG) are promoted.…”