Non-radiative energy transfer from Er 3+ ions to the electronic states of the chalcogenide glass matrix

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

“…The nonradiative energy transfer from the glass matrix to REI has been demonstrated in chalcogenide glasses doped with REI from photoluminescence and photoluminescence excitation spectroscopy [16][17][18]. The energy backtransfer has been found from the lifetime measurement in Ga-Ge-S : Er 3+ glasses [19,20]. However, to the best of our knowledge the energy backtransfer in REI doped chalcogenide glasses has not been observed from the measurement of the glass matrix conductivity as yet.…”

“…In this case, three levels of Er 3+ can contribute to the photoconductivity. Furthermore, the lifetime of the level 4 S 3/2 exceeds by several times those of the levels 4 F 7/2 and 2 H 11/2 [19,20]. Therefore, the relatively high photoconductivity of the third glass can be explained by a higher probability of the energy transfer from the level 4 S 3/2 as compared with the levels 4 F 7/2 and 2 H 11/2 .…”

“…The other way to determine the contribution of Er 3+ ions to the photoconductivity is to examine the effect of the optical band-gap energy of the glass matrix on the lifetime of erbium levels. In the paper [20] the above-described glasses have been studied using lifetime luminescence spectroscopy. In particular, the lifetime of the levels 4 S 3/2 and 4 F 9/2 has been measured.…”

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.…”