Solid-state tunable kHz ultraviolet laser for Raman applications

Performance characteristics are described for a kilohertz solid-state laser source for resonance Raman spectroscopy. Narrow line excitation in the 205 -230 nm region is provided by quadrupling a titanium:sapphire laser which i s pumped by the second harmonic of a Q-switched YLF laser. The combination of tunability, narrow line, high average power, and good stability makes th is laser suitable for ultraviolet resonance Raman (UVRR) applications. UVRR spectra of hemoglobin, excited at 229 nm, are as high in quality as those produced by continuous-wave intracavity frequency-doubled Ar+ laser excitat ion. Raman excitation profiles are reported for aromatic acids in aqueous s olution and in hemoglobin.