Isotopic gas analysis through Purcell cavity enhanced Raman scattering Available to Purchase

Purcell enhanced Raman scattering (PERS) by means of a doubly resonant Fabry-Perot microcavity (mode volume ≈ 100 μm³ and finesse ≈ 30 000) has been investigated as a technique for isotopic ratio gas analysis. At the pump frequency, the resonant cavity supports a buildup of circulating power while simultaneously enabling Purcell spontaneous emission rate enhancement at the resonant Stokes frequency. The three most common isotopologues of CO₂ gas were quantified, and a signal was obtained from ¹³C¹⁶O₂ down to a partial pressure of 2 Torr. Due to its small size and low pump power needed (∼10 mW) PERS lends itself to miniaturization. Furthermore, since the cavity is resonant with the emission frequency, future improvements could allow it to serve as its own spectral analyzer and no separate spectroscopic device would be needed.