Direct surface relief formation in As-S(Se) layers

Dual Effects of Photo-Darkening and Photo-Bleaching in Ge-Se Films

“…The most significant change of the optical parameters was observed for the annealed Ge 33 Se 67 film, while of the thickness change was more remarkable for the annealed Ge 28 Se 72 . It is worth mentioning that the change of the thickness due to irradiation in the annealed samples was found to be larger than in the as-prepared ones.…”

“…Note that the process reaches saturation after about 400 s for the Ge 28 Se 72 and after about 1,800 s for the Ge 33 Se 67 compositions at the given illumination conditions.…”

“…Increase of the thickness was detected in both PD and PB states for all the samples, and it was found to be prominent in the PD state. It was established that a more significant change in the optical parameters occurs for the Ge 33 Se 67 sample, while the Ge 28 Se 72 layer exhibited the largest change in the thickness during illumination.…”

“…The ES peak area decreases (the change is more remarkable in the PD state), the CS peak area increases (more significantly in the PD state). The ETH peak area decreases due to laser irradiation (relevant for Ge 33 Se 67 and Ge 40 Se 60 samples only).…”

“…The kinetics of the transmission change under laser illumination was detected in situ by Newport and Thorlabs power meter setups. In fact, since the absorption edge and light sensitivity of the prepared samples depend on the films composition, its structure and Ge concentration [18], Ge 28 Se 78 and Ge 33 Se 67 samples were illuminated with laser setup operating at 533 nm with output power of 8.5 mW, while the Ge 40 Se 60 sample was irradiated with laser setup operating at 633 nm with an output power of 12 mW. The samples were irradiated through a 2 mm aperture.…”