Le Laboratoire Temps Espace

The Laboratoire Temps Espace (LTE) was created on January 1, 2025. It is the result of the merger of two former Paris Observatory entities: SYRTE (SYstèmes de Référence Temps-Espace) and IMCCE (Institut de mécanique céleste et de calcul des éphémérides). LTE and is also associated with the CNRS (National Research Center), the Sorbonne Université and the LNE.
LTE is a leader in time and frequency metrology and is also specialized in Earth rotation, celestial reference frame and history of Astronomy. LTE has a multidisciplinary research activity with expertise in theory, instrumentation and data analysis and various goals from fundamental physics tests to industrial transfers. It is  a founding member of Laboratoire d’Excellence du Programme Investissements d’Avenir FIRST-TF.

The optical frequency metrology within LTE has developed some of the most precise strontium optical lattice clocks in the world. 

Team members

Jérôme Lodewyck is a CNRS research at LTE, Observatoire de Paris. He has worked on Sr optical lattice clocks since 2007, with the objective of improving the stability and accuracy of these clocks. His activities encompasses the metrological applications of these clocks (contributions to the International Atomic Time, frequency ratio measurements, redefinition of the SI second, test of fundamental physics), as well as the use of quantum entanglement in lattice-trapped atoms.

Contact: [email protected]

Rodolphe Le Targat is staff researcher at LTE, Observatoire de Paris, since 2011. He leads frequency combs activities, together with the development of infrared ultrastable lasers at 1542 nm. He also coordinates the construction of a transportable optical lattice clock based on neutral ytterbium.

Contact: ​[email protected]