Laser-induced piezoelectric effects in chalcogenide crystals

The photoinduced piezoelectric effect in the single crystals of AgGaGe3Se8 was discovered under the influence of 532 nm cw laser with average power about 150 mW. The changes of the piezoelectricity were explored with respect to principal diagonal components d11, d22, and d33. To study the contributions of photostimulated thermal and piezooptical effects additional measurements of temperature dependent piezoelectricity and piezo-optical coefficients were done. Substantial changes were demonstrated and their time kinetics during photoillumination was explored. The three principal diagonal piezoelectric coefficients along the crystallographic axis were studied. The reversibility of the process after switching off of the photoinducing laser is given. The effect observed may be applied for laser operated piezotronic devices. The contribution of different mechanisms in the photostimulated piezoelectricity is explored.