Lab: Laboratoire de Physique des Lasers (LPL), MMTF group and LNE-SYRTE, Optical frequencies metrology group.
Optical fiber links were developed in the last decade to transfer an ultrastable frequency reference over hundreds of km, with a minimal degradation of its stability and accuracy performance . It consists of transmitting an ultrastable laser, which frequency is controlled with atomic clocks, through an optical fiber to the remote lab, with an active compensation of the propagation phase noise. We demonstrated that the transferred signal frequency is copying the input signal frequency with residual fractional unstabilities below 10-15 at 1-s averaging time . The long-term stability can reach the 10-20 range.
(Université Paris 13, CNRS) and LNE-SYRTE (Observatoire de Paris, CNRS, UPMC) have pioneered the development of optical links for applications both in time and frequency metrology and in high-precision measurements. We have recently demonstrated two international links to Germany and UK in order to compare the best optical clocks of these countries with the clocks developed at SYRTE . We are also developing a national metrological network to transfer an ultrastable frequency signal to 20 labs over France  and are currently transferring our know-how to three French companies.
Our next objectives aim at applying such optical links to very precise comparison of distant oscillators and chronometric geodesy, and more generally some advanced tests of physics, including search for dark matter. For this purpose, the fundamental and technological limits of the frequency transfer should be assessed . The postdoctoral researcher will in particular study the effects of polarisation and amplification on the noise correction and long-term stability. He or she will develop an experimental set-up using as some fiber spools and the two parallel urban 43-km fibers linking LPL and SYRTE. He or she will also pursue our current work concerning the link stability and accuracy analysis with non-continuous phase transfer. These studies will also benefit from stability data of our long-haul links and will contribute in return to the upgrade of the link between LPL and London and to the development of new fiber links between Paris and Besançon.
The post-doctoral researcher will work at LPL, with deep collaboration with SYRTE lab. He or she will be involved in our national and international collaboration networks.
The candidates should have a PhD related to optics, laser-matter interaction, or optoelectronics with excellent experimental skills. Knowledge in noise analysis and fiber optics is obviously a strong asset. Experience in laser frequency stabilisation, electronics or signal processing is beneficial.
Applicants should address by e-mail to Pr. A. Amy-Klein a curriculum vitae, a list of publications, the name of 2 referees (with e-mail and affiliation) and a cover letter. One-year post-doc starting between November 2017 and February 2018, with possibility of 1 or 2 years extension.
 O. Lopez et al., Comptes Rendus Physique, 16, 531-539 (2015).
 N. Chiodo et al., Optics Express, 23, 33927-33937 (2015).
 C. Lisdat et al, Nature Communications 7, 12443 (2016).
 W. K. Lee et al, Appl. Phys. B 123, p 161 (2017).