Generation of 12 fs deep-ultraviolet pulses by four-wave mixing through filamentation in neon gas

摘要

Generation of deep-ultraviolet femtosecond pulses by four-wave mixing through filamentation in neon gas was demonstrated. Fundamental (omega) and second-harmonic (2 omega) pulses of 25 fs Ti:sapphire amplifier output were focused into neon gas, and 20 mu J pulses with the center wavelength of 260 nm were produced by a four-wave mixing process, 2 omega+2 omega-omega ->omega through an similar to 15 cm filament. Additionally, pulses with an energy of 2 mu J at 200 nm were generated, probably by a cascaded process, 3 omega+2 omega-omega -> 4 omega. The 260 nm pulses were compressed by a grating-based compressor and characterized by a dispersion-free transient grating frequency-resolved optical gating. The estimated pulse width was 12 fs. (c) 2007 Optical Society of America.