Research departments


"OHMS" TEAM : Waves, Clocks, Metrology and Systems

(Ondes, Horloges, Métrologie et Systèmes)

Click here for more information concerning the OHMS team

Team leader

Rodolphe BOUDOT


Our OHMS team works in the production of secondary frequency standards and metrological characterization of oscillator phases and frequency fluctuations. It is also a partner in the network FIRST-TF and the Equipex REFIMEVE+.

Goals and Research Areas

The team has developed three broad themes:

› Microwave frequency references
- Cryogenic sapphire oscillators
- Atomic micro- and compact clocks

› Optical frequency references
- Stabilized lasers and low-noise microwave signal generation
- Trapped ion optical clock
- Connection to the REFIMEVE+ network

› TF instrumentation and metrology
- Digital electronics
- Improvement and monitoring of calibrating potential for the LNE LTFB


The OHMS team is one of only two teams in the world proficient in the technology of cryogenic sapphire oscillators. It enjoys international recognition for its work on ultrastable oscillators and phase noise metrology, and was the initiator of the atomic clock micro-project in Europe.

Implementing our work

Locally, the team can count on the other departments of the FEMTO-ST Institute (especially MN2S and OPTIQUE) to participate in transdisciplinary interdepartmental projects. It has also collaborated for many years with the LNE-SYRTE at the national level and has forged strong collaborative relationships with university and industrial partners (IEMN, CEA LETI, etc.) worldwide.