History

Based on a major technological breakthrough, REFIMEVE (Réseau Fibré Métrologique à Vocation Européenne) is a national research infrastructure coordinated by the Laboratoire de Physique des Lasers (LPL) – CNRS and Université Sorbonne Paris Nord – and the LTE – Paris Observatory-PSL, CNRS, Sorbonne University, LNE – with support from RENATER.

Using RENATER’s optical fiber network, REFIMEVE transmits ultra-stable time and frequency signals developed by LTE, France’s national time-frequency metrology laboratory. These signals maintain a precision level better than 10^-18. The REFIMEVE network currently spans 9,000 km of optical links and connects to major European metrology institutes and CERN. It enables the distribution of an ultra-stable frequency signal to more than 30 laboratories across France. The network includes optical signal regeneration stations, with prototypes developed at LPL and LTE, now commercialized by the company Exail

The infrastructure has been developed primarily through two “Programme d’Investissement d’Avenir” (PIA) projects: REFIMEVE+ (2012) and T-REFIMEVE (2021). A European-scale expansion is being studied through the CLONETS-DS (Clock Network Services – Design Study) project.

Equipex REFIMEVE+ (2012-2023)

The REFIMEVE+ Equipex project was coordinated by LPL, in partnership with LTE and RENATER, and led by Université Sorbonne Paris Nord (USPN). It enabled the creation of a fiber network linking LTE to some fifteen French laboratories, as well as to PTB (Germany), INRIM (Italy), and NPL (UK). The ultra-stable optical frequency signal distributed from LTE supports diverse applications: time/frequency metrology, fundamental physics (on Earth and in space), precision spectroscopy for environmental and atmospheric studies, and seismology.

REFIMEVE equipment was developed by three French companies through a technology transfer agreement managed by LPL and LTE.

Equipex T-REFIMEVE (2021-2029)

The T-REFIMEVE Equipex project is coordinated by USPN with 24 partners including CNRS and RENATER, and is led by LPL and LTE. It aims to extend REFIMEVE to 30+ French laboratories and several major research infrastructures: SOLEIL, IRAM, ESRF, and CERN.

Beyond optical frequency transfer, T-REFIMEVE provides radiofrequency and ultra-stable time signals using the White Rabbit protocol and, eventually, high-performance time transfer technologies. This significantly broadens the scientific applications: spectroscopy, astrophysics, synchronization, VLBI, geodesy, seismic monitoring, quantum technologies, and more.

Crédit : CNRS – LPL