Spectral Dependence of the Photoplastic Effect in CdZnTe and CdZnTeSe

We studied the spectral dependence of the Vickers microhardness HV0.025 of CdZnTe and CdZnTeSe samples upon illumination and found out that it increases over the entire applied spectral range of 1540–750 nm. We also found out that the photoconductivity and microhardness are correlated. We observed changes in the correlation diagram (change of slope and an abrupt change of HV0.025 at several wavelengths of the illuminating light). Based on measurements of the relative changes of the space charge upon illumination using the Pockels effect, we suggest that the observed spectral dependence of positive photoplastic effect in CdZnTe and CdZnTeSe can be explained by the trapping of photoinduced electrons and holes, which affects the motion of the partial dislocations. The underlying physical explanation relies on the assumption that reconstructed bonds break before dislocation glide.

Влияние освещения на пьезоэлектрические характеристики кварцевых резонаторов

The results of the effect of lighting on the piezoelectric characteristics of quartz resonators in the form of a tuning fork, which have been pre-trained by increased friction from the external environment, are presented. A significant change in the piezoelectric characteristics of such resonators was found depending on the intensity and spectrum of illumination. It is assumed that the detected change in the characteristics of the resonators is due to dislocations formed in the resonator during training with increased friction of the external environment, and is a manifestation of the well-known photoplastic effect and its quenching.

Light-Induced Structural Relaxation and the Photoplastic Effect in Chalcogenide Glasses

The combination of depth-sensing indentation and band-gap illumination has been used to study the photoplastic effect (the reversible influence of light on the flow stress, hardness, and plasticity) in chalcogenide glasses on a nanoscale. The prominent photoplasticity of thin As-Se films has been revealed through deviations in the shape of load-displacement curves during nanoindentation under light illumination from those ones which have been observed for the material in the darkness. The photoinduced changes in static mechanical properties such as nanohardness and elastic (Young’s) modulus have been determined. The highest photoplasticity changes are achieved for As20Se80 films while their photodarkening is the lowest.