Generation of sub-10 fs ultraviolet Gaussian pulses

A technique is proposed for generating sub-10fs deep ultraviolet (DUV) pulses with Gaussian temporal and spectral profiles. In this approach, a broadband DUV pulse with a negative frequency chirp is generated and compressed by normal group-velocity dispersion in a transparent medium. The pulse shape is not significantly distorted by high-order spectral phase distortion. In principle, nearly transform-limited sub-6fs UV pulses with pulse energies of several tens of microjoules are expected to be generated. Numerical simulations indicate that a Ti:sapphire chirped-pulse amplifier with a pulse energy of several millijoules and a pulse duration of 35fs can be used to generate high-energy sub-6fs UV pulses. The technique is partially demonstrated by an experiment using a low-power Ti:sapphire chirped-pulse amplifier to generate low-energy sub-10fs single DUV pulses with waveforms that quantitatively agree with those predicted by the numerical simulations. This technique can be used to generate high-energy sub-10fs DUV pulses with Gaussian temporal and spectral profiles for ultrafast spectroscopy in the gas phase as well as the liquid and solid phases.