Color center formation and electronic excitation processes in superionic crystals RbAg4I5

The effect of photoinduced reversible coloration was discovered and investigated in superionic RbAg 4 I 5 crystals exposed to light irradiation 2.92 eV ≤ hv ≤ E g = 3.2 eV at T = 300 K. Spectral efficiency measurements of the photoinduced effect let to the discovery that profound changes in the absorption spectrum of RbAg 4 I 5 crystals are observed on 2.92 eV light irradiation. Relaxation of the photoinduced absorption after cessation of the irradiation was found to be of exponential form with a time constant of about 900 s. The mechanism of the photoinduced coloration is considered to be due to self-trapped holes injection under the irradiation of RbAg 4 I 5 superionic crystals.