Abstract

Coherent radiation in the extreme ultraviolet (XUV) wavelength domain is generated by non-linear upconversion (third and fifth harmonic generation) of the output of powerful Nd-YAG pumped and frequency-doubled dye lasers. Continuous tunablity in the range 54-100 nm is established. With the use of a pulsed-dye-amplifier (PDA) nearly Fourier-transform limited pulses are produced, which after upconversion into the XUV have bandwidths < 300 MHz. An advantage of the application of harmonic generation is the possibility of on-line frequency calibration in the visible, resulting in accurate calibration of the XUV-frequencies.

© 1996 IEEE