Abstract

Atomic spectroscopy using broadband ultrashort laser pulses with durations in the 100-fs range seems nearly impossible because the large bandwidth of the pulses exceeds the line-width of atomic transitions by several orders of magnitude. Therefore the energy loss of ultrashort pulses crossing a narrow-linewidth medium is very low, even if the center frequency of the pulses is tuned to the transition frequency. For instance, the total absorption of a 100-fs pulse centered at the D₂-absorption line of Rubidium near 780 nm is well below 10^-3 if the pulse is sent through a 75-mm-long Rb vapor cell at room temperature.

© 1996 Optical Society of America