SBS-compressed FT-limited laser pulses tunable in wavelength and duration (200-2000 ps)

Using Fourier-transform (FT) limited laser pulses, structural and dynamical information can be retained from gas, liquid and solid-phase samples. In many cases it is, however, practical to reduce the bandwidth such that the relevant spectral structures are resolved, and then use the resulting temporal response of the optical pulses to derive dynamical information on the spectrally resolved structures. Using a wavelength-tunable pulsed-dye amplifier and pulse compression, the resulting pulse duration can be varied in the range 400-2000 ps. The resulting pulse duration is governed by the power density of the incident beam, which can be varied by the changing beam diameter. Pulse compression is established by the process of Simulation Brillouin Scattering (SBS). From the spectral and time domain measurements, it is demonstrated that the SBS-conversion efficiency is >80%