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)