Giant static electric field in photo-darkened CdS Se1 − semiconductor doped glasses

The giant static electric field generated in II–VI semiconductor doped glasses during the photo-darkening process is studied through the time-resolved measurement of Bragg diffraction efficiency of the refractive index gratings photo-induced in the material. This technique allows a precise determination of the photo-darkening fluence threshold. Results obtained in samples of different compositions demonstrate the intrinsic behaviour of this photo-darkening effect and show that this process originates more likely from the Auger effect which occurs at high write fluences. The annihilation of the static electric field of ionized dots by extra electron-hole pairs is also demonstrated unambiguously.