Fig. 1. (a) Experimental scheme of irradiation setup for in situ measurements. A pump beam from a DPSS laser is aimed onto the sample through the plano–convex lens, and its desired optical intensity is adjusted by the neutral density filter(s) (ND). (b) Typical time evolution of absorption coefficient Δα(t) for as-deposited film (black) and annealed film (red) upon room-temperature irradiation at laser optical intensity of 125  mW·cm−2; shaded region represents the data acquisition after the laser is switched off; insets with photodarkened (top) and photobleached (bottom) University of Pardubice logo using 1 mm diameter negative stencil (colors are illustrational only without profiling).

Fig. 2. Time evolution of absorption coefficient Δα(t) of as-deposited (top panel) and annealed (bottom panel) Ge-Sb-Se thin films upon room-temperature irradiation depending on thicknesses (in nm) at different laser optical intensities varying from 3 to 125  mW·cm−2.

Fig. 3. (a) Time evolution of absorption coefficient Δα(t) of as-deposited and (b) annealed Ge-Sb-Se thin films with thickness of ∼650  nm depending on the laser optical intensity. (c) On/off cycle (240 s) experiment with as-deposited (black line) and annealed (red line) Ge-Sb-Se thin films with the same thickness using laser optical intensity of 50  mW·cm−2. The shaded area corresponds to the cycle when the laser is switched on.

Fig. 4. (a) Normalized reduced intensity of Raman spectra of nonirradiated as-deposited and (b) nonirradiated annealed Ge-Sb-S thin films.