HCOOH high resolution spectroscopy in the 9.18$\mu$m region

Franck Bielsa (1, 2) , Khelifa Djerroud (3) , Andrei Goncharov (3) , Albane Douillet (1, 2) , Tristan Valenzuela (1, 2) , Christophe Daussy (3) , Laurent Hilico (1, 2) , Anne Amy-Klein (3)

1 LKB (Jussieu) - Laboratoire Kastler Brossel
2 DPM - Département de Physique et Modélisation
3 LPL - Laboratoire de Physique des Lasers

We report on higly accurate absolute frequency measurement against a femtosecond frequency comb of 6 saturated absorption lines of formic acid (HCOOH) with an accuracy of 1~kHz. We also report the frequency measurement of 17 other lines with an accuracy of 2~kHz. Those lines are in quasi coincidence with the 9R(36) to 9R(42) CO$_2$ laser emission lines and are probed either by a CO$_2$ or a widely tunable quantum cascade laser phase locked to a master CO$_2$ laser. The relative stability of two HCOOH stabilized lasers is characterized by a relative Allan deviation of 4.5~10$^{-12}$~$\tau^{-1/2}$. They give suitable frequency references for H$_2^+$ Doppler free two-photon spectroscopy.

Keywords: laser à cascade quantique; acide formique; HCOOH; spectroscopie; mesure de fréquence

Domains: Atomic Physics [physics.atom-ph]

Franck Bielsa, Khelifa Djerroud, Andrei Goncharov, Albane Douillet, Tristan Valenzuela, et al.. HCOOH high resolution spectroscopy in the 9.18$\mu$m region. 2007. ⟨hal-00162635⟩