München 2004 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
Q: Quantenoptik und Photonik
Q 49: Ultrakurze Lichtimpulse: Quantenkontrolle (gemeinsame Sitzung mit Fachverband MO)
Q 49.2: Talk
Friday, March 26, 2004, 11:15–11:30, HS 223
Control of phase and amplitude of 10 to 20 fs laser pulses tunable in the visible spectral range — •Stephan Malkmus, Constanze Sobotta, Jörg Neuhaus, Regina Dürr, and Markus Braun — Ludwig-Maximilians-Universität München, Lehrstuhl für BioMolekulare Optik, Oettingenstraße 67, 80538 München
Wavepaket motions can be studied to gain temporal and structural information of molecular movements from optical spectroscopy (besides fs-time-resolved X-ray, raman and IR methods). Tunable pulses in the 10 fs range are a prerequisite for resolving high frequency modes above 1000 cm−1.
We present a procedure of phase and amplitude optimisation of superbroad tunable ultrashort pulses generated by a non-collinear optical parametric amplifier (NOPA). This is obtained both, by direct crosscorrelation-FROG diagnostics and correction of the spectral phase in the Fourier plane of a 4-f-setup with a liquid-crystal mask (No-dqpulse-shaperNo-dq), and by an evolutionary algorithm optimising the broadband second harmonic signal in order to get the shortest pulses.
The application of these pulses for the measurement of wavepaket motions in an oxazine dye will be presented.