The structural changes in the semiconductor indium antimonide (InSb) after the excitation with an ultrashort laser pulse (60 fs) are investigated, by using ultrashort x-ray pulses (100 fs) from a laser plasma X-ray source. To characterize the emitted radiation, a novel Timepix detector is used, which was capable to detect bremstrahlung up to 700 keV.

By using a strong asymmetric Bragg reflection it was possible to adapt the extinction depth of the X-rays to the absorption depth of the optical laser pulse used for excitation. This small extinction depth made it possible to measure 2 ps after excitation a strain of 4% in a 4 nm thin layer on the surface. The excitation of the semiconductor is described with different theoretical models, the predicted temporal and spatial evolution of the strain is compared with measured results.

Seminarraum HI-Jena, Fröbelstieg 3
Datum (Start der Veranstaltung)