Harmonic generation with temporally focused ultrashort pulses

The properties of harmonic generation with temporally focused ultrashort pulses are explored both theoretically and experimentally. Analyzing the phase-matching conditions for harmonic generation we find a correspondence between temporal focusing and spatial focusing along one dimension. In particular, temporally focused pulses experience a pi phase shift in passing through the temporal focus, similar to the Guoy phase shift experienced by spatially focused beams. This correspondence is confirmed by measurements of third-harmonic generation induced by temporally focused pulses. (c) 2005 Optical Society of America