We perform laboratory experiments to study ultraviolet radiation generated by intense self-formed laser filaments produced by propagating high-power femtosecond laser pulses in air. The laser used in the experiment is a 0.5 TW Ti:sapphire system with the center wavelength at 800 nm. The observed ultraviolet emission occurs in the form of the third harmonic and frequency-upshifted radiation from the fundamental. We present direct characterization of the generated harmonic and frequency-upshifted radiation, including transverse imaging and spatially resolved spectral measurements.
© 2005 Optical Society of America
I. Alexeev, A. C. Ting, D. F. Gordon, E. Briscoe, B. Hafizi, and P. Sprangle, "Characterization of the third-harmonic radiation generated by intense laser self-formed filaments propagating in air," Opt. Lett. 30, 1503-1505 (2005)