Radiative recombination in vitreous and single crystal As2S3 and As2Se3

Photoluminescence and optical absorption in glassy AsxSe1−x

“…1 and the absorption spectra as shown in Fig. 6 are fairly similar to one another and agree with previous results [17][18][19][20][21]. The PL peak energies appear at approximately half the optical gap, and the optical absorption spectra exhibit an exponential dependence on energy whose exponential slopes are approximately 75 meV.…”

“…Also shown in Fig. 4 are literature values for x = 0.0, 0.40, and 1.0 [17][18][19][20][21]. The solid circles illustrate the behavior of the optical gaps as a function of x (energy where a = 10 4 cm À1 ).…”

“…The occurrence of the PL peak at approximately half the optical gap for x 6 0.4 is also apparent. [17][18][19][20][21]. The inset shows the discontinuous change in the PL peak energy near x = 0.4.…”

Preparation and characterization of telluride glasses

“…The large difference between the PL peak and the optical band gap E g is the indication that deep states are involved in the recombination. It has been suggested [8] that observed transitions are from band tails to states near the middle of the gap. This broad band starts to quench above 200 K and a new band appears at 900 nm.…”

Low-temperature photoluminescence in chalcogenide glasses doped with rare-earth ions

“…The broad-band host-glass PL, mediated by the presence of deep energy states in the band-gap, is centred at about the mid-band-gap energy, is strongly dependent on temperature, and it is usually observed only at low-temperature [18][19][20][21]. On the other hand, the 4f-4f inner shell transitions exhibit little temperature dependence and are readily observed at room temperature.…”