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Reference : UMR7538-BENDAR-004
Workplace : VILLETANEUSE
Date of publication : Friday, February 07, 2020
Type of Contract : FTC Scientist
Contract Period : 6 months
Expected date of employment : 1 April 2020
Proportion of work : Full time
Remuneration : minimum 2695 € per month gross salary (without any experience)
Desired level of education : PhD
Experience required : Indifferent
The postdoctoral researcher will integrate the 'Metrology, Molecule and Fondamental Tests' team (MMFT) of Laboratoire de Physique des Lasers (LPL). He/She will work within the framework of a project dedicated to the development of a spectrometer dedicated to ultra-precise measurements in the mid-infrared spectral region.
Ultra-high resolution molecular spectroscopy is an interdisciplinary field with fascinating and far-reaching applications ranging from fundamental physics to Earth and planetary science, and to astrophysics and cosmology. The mid-infrared domain, the so-called molecular fingerprint region, is a crucial spectral window which hosts a considerable number of intense vibrational signatures of species of various interests.
This project focuses on the development of new-generation QCL (quantum cascade laser) based spectrometers specifically designed for precision vibrational spectroscopy in the mid-infrared (8-11 µm). Since a few years, LPL has developed ultra-high resolution spectrometers based on highly stable mid-infrared quantum cascade lasers locked to an optical frequency comb itself stabilised on a frequency reference in the optical domain (1542 nm) provided through an optical fibre link. This frequency reference is given by an ultra-stable laser located at SYRTE, the French time-frequency metrology institute, where it is calibrated to some of the world's best primary frequency standards. to the reference signal from SYRTE. The objectives of the project consist in improving the current experimental setup in terms of spectral resolution, tuneability, spectral coverage, detection sensitivity and flexibility. The proposed technology is at the forefront of time-frequency metrology and will be used to perform tests of fundamental physics and explore the limits of the standard model (measurements of variation of fundamental constants, tests of fundamental symmetries), as well as to carry out spectroscopic measurements of interest to atmospheric physics and astrophysics at unprecedented levels of precision.
- The successful candidate will first have to familiarize with the existing experimental setup.
- He/She will actively participate in improving it: improvement of the spectrometer tuneability, resolution and detection sensitivity, and extension of its spectral coverage. This will require the setting up of new spectroscopic devices (cavities, cells…) and associated vacuum systems, developments in both fibred and free space optics, in electronics (servo-loops) and in programming (data acquisition, device control).
- He/She will participate in the exploitation of the experimental setup for precise spectroscopic measurements on a variety of molecular systems of interest for astrophysics or atmospheric physics (ammonia, ethene, methanol, sulphur hexafluoride, dimethyl sulphide…). He/She will have to measure the absolute frequency of a few transitions with a sub-kHz uncertainty, or even at the few 10-Hz level and study pressure shift effects on the probed lines. He/She will also exploit the spectrometer for fundamental physics applications, in particular for the spectroscopy of chiral orgao-metallic species for which the frequency differences resulting from the parity violation inherent to the weak interaction may ne measurable.
- The applicant should have a PhD in a relevant area of experimental physics or chemical physics: molecular, atomic physics, spectroscopy, optics and lasers, quantum optics.
He/She will be expected to take an active role in the operation and development of this experimental activity and in all other aspects of the project:
- sourcing and ordering of equipment;
- management, planning and prioritisation of the research activity;
- day-to-day guidance of graduate and undergraduate students;
- development of the collaborations with other project partners;
- attendance at national and international conferences;
- article writing.
This activity takes place at the Laboratoire de Physique des Lasers (UMR 7538 CNRS-Université Paris 13), in Villetaneuse, within the 'Metrology, Molecules and Fundamental Tests' team (MMFT, http://www-lpl.univ-paris13.fr/UK/EQUIPE-MMT-PRESENTATION.awp). The project is conducted in collaboration with LNE-SYRTE (CNRS-Observatoire de Paris): we benefit from a frequency reference provided by LNE-SYRTE and transmitted to the LPL via an optical fibre. The project is supported by labex First-T, ANR and Île-de-France region.
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