Mode-locked cavity-enhanced absorption spectroscopy

The authors demonstrate the cavity enhanced absorption spectroscopy technique with a frequency doubled ML Ti:Sa laser and a much better spectrograph (resolving power >200000), to study absorption by nitrogen ions in a plasma around 390 nm. In addition, they are implementing electronic locking to the magic point resonance which greatly increases signal level and will allow obtaining (and reporting) ML-CEAS measurements with much higher cavity finesse: F > 5/spl times/10/sup 5/.