1C4 - Infrared difference frequency generation

Several molecular vibrational frequencies have been generated by beating together a laser and laser-stimulated Raman emission. A Nd³⁺/glass laser was used to excite Raman emission from C6H6, C6D6, and CH3. NO2. The difference frequencies were generated in a single crystal of CdS and appeared at 992, 944, and 927 cm^-1, respectively. A difference frequency has also been detected at 944 cm^-1following mixing in CdSe. The data presented for HgS indicates that phase-matched outputs can be generated over a limited range of frequencies, provided that the Raman emission is excited with a Nd³⁺/glass laser. Experimental details are given and the results are discussed.