Mechanism of photochromic effect in Pb(Zr,Ti)O3 and (Pb,La)(Zr,Ti)O3 ceramics under violet/infrared light illumination

Obvious photochromic effects were observed in Pb(Zr,Ti)O-3 and (Pb,La)(Zr,Ti)O-3 (PLZT) ceramics, along with exponential responses to illumination power in both darkening and bleaching processes. An interesting anomalous dispersion in the transparent PLZT was observed and discussed. A tentative physical picture based on photoinduced electron stimulated processes and on structural change was proposed to explain all the interesting observations. Rate equations were established and solved in verifying the validity of the proposed model. This work may serve as guidance in designing tunable achromatic lenses, UV and IR light detectors and sensors. (C) 2015 AIP Publishing LLC.