Shaping of wide bandwidth 20 femtosecond optical pulses

We investigate the propagation of 20 fs pulses through a generalized pulse shaper/compressor and synthesize shaped waveforms with 20 fs features by linear spectral filtering using a generalized pulse shaper consisting of gratings and reflective optics. The use of reflective optics in the pulse shaper avoids cubic phase dispersion associated with lenses which significantly broaden short 20 fs pulses. As an example of our pulse-shaping capabilities, we generate pulse trains with repetition rates in excess of 12 THz using phase-only filtering.