Multiphoton excitation of molecules by single mode CW lasers

Abstract

An intracavity laser interaction zone with molecules expanded in a molecular beam set-up permits multiphoton excitation under collision-free conditions by narrow band radiation. Two- and three-laser experiments are performed to study rapid adiabatic passage processes, stimulated de-excitation and hole burning effects. The detection of excitation occurs by means of a sensitive bolometric molecular beam detector. The essential information obtained for SF 6 concerns the vibrational bottleneck, the conservation of excited eigenstate characteristics for at least 1 ms, the ease with which about 15 photons can be deposited in the molecules with the help of two cw CO 2 lasers and the influence of simultaneous two-frequency radiation, yielding a significant extra-excitation. Other molecules where multiphoton excitation is observed utilizing the same set-up are CF 3I and CF 3Br.