Erbium-mediated photoconductivity of Ga–Ge–S–Se : Er³⁺chalcogenide glasses

Abstract

Photoconductivity mediated by erbium ions in chalcogenide glasses Ga–Ge–S has been found. The conductivity of glasses undoped and doped with erbium has been studied under irradiation by laser light at λ = 813 nm. In both cases the optical band-gap energy exceeds by several times the laser photon energy. It has been observed that the exposure to sub-band-gap light does not change the conductivity of the undoped glass, whereas it leads to a significant increase in the conductivity of the glass doped with erbium. We propose a two-photon mechanism of the photoconductivity in this glass, where erbium accumulates laser energy and then transfers it nonradiatively to the glass matrix (energy backtransfer).

Greater than 50% inversion in Erbium doped Chalcogenide waveguides

“…Due to the small mode area (~2 µm 2 ) of the waveguides, the intensity of up-conversion related emissions in the waveguides could certainly be high enough to induce photoinduced absorption, and this coupled with the insensitivity to high power 1430 nm light strongly suggests this is the cause of the increased loss. In addition, Er 3+ ions excited to sates with energy equal to or higher than the bandgap energy of the glass matrix may directly transfer energy to the electronic states of the glass matrix [27,28]. This may also be a contributor for the observed photo-induced loss, but data is not reported on such optical loss.…”

Structure of rare-earth chalcogenide glasses by neutron and x-ray diffraction

“…optoelectronic devices [7, 11, 13, 15-18, 20, 21, 23, 25-42]. There have been comparatively few investigations of the corresponding selenide or mixed sulphide/selenide glasses [9,[40][41][42][43][44][45][46][47][48].…”