Thermal and non-thermal processes in the photostrictive response of ferroelectric GeTe thin films with sub-nanosecond time-resolution

Using light to control complex systems on ultra-short timescales provides a powerful tool to probe fundamental phenomena in thin films and is promising for future applications. In this proposal we aim at addressing the light-induced response of ferroelectric/ferroelastic GeTe single crystalline thin films with sub-nanosecond time resolution. In order to study the photostrictive properties of GeTe we plan to perform time-resolved x-ray diffraction and measure symmetric and asymmetric Bragg peaks. By analysing the switching dynamics of ferroelastic domains in GeTe as well as the dynamics of shear and longitudinal strain components as function of laser fluence and film thickness we will address the contributions of thermal and non-thermal processes resulting from the photoexcitation of charge carriers.