A New Picosecond Source in the Vibrational Infrared

Abstract

The successful generation of picosecond pulses in the vibrational infrared by stimulated electronic Raman scattering (SERS) of visible pulses from an amplified synchronously pumped dye laser operating with rhodamine dyes is reported^l. The simplicity and efficiency of SERS as a frequency shifting technique have been amply demonstrated with nanosecond pulses²⁻⁴. SERS has the advantages of using a non-damageable medium and having no phase-matching requirements. Cotter and Wyatt have shown that picosecond SERS from the cesium 6s–7s transition (see Fig. la) can generate infrared even more efficiently than the corresponding nanosecond process⁵.However, the practical utility of their system was limited by the difficulty in generating high power picosecond pump pulses in the blue-green. Because of this difficulty, a SERS technique based on a reliable synchronously pumped dye laser operating with rhodamine dyes is desirable.