Missions

Ultra-high resolution molecular spectroscopy and frequency metrology using cutting-edge mid-infrared technologies

The project focuses on the development of ultra-high-resolution molecular spectrometers, employing cutting-edge mid-infrared (mid-IR) technologies. It is part of the project CORALI (COherent mid-infrared RAdiometry and LIdar for atmospheric remote sensing) funded by ANR. The successful applicant will be shosted at Laboratoire de Physique des Lasers (LPL), under the supervision of B. Darquié.

Key words: mid-infrared photonics, ultra-high resolution vibrational spectroscopy, frequency metrology, quantum cascade lasers, frequency comb lasers, Doppler-free spectroscopy, Ramsey interferometry, precision measurements, molecular physics, quantum physics, quantum optics, cold molecules, buffer-gas cooling, molecular beams, optics and lasers, vacuum techniques, electronics, microwave, cryogenics, programming and simulation.

Activities

LPL develops high-resolution spectrometers for precision vibrational spectroscopy of cold and room-temperature species in the gas phase for improving tests of fundamental physics and precision measurements in general. The successful applicant will work on exploiting cutting-edge mid-IR technologies in this context. Such technologies include (i) laser sources: sub-Hz mid-IR quantum cascade lasers (QCLs), mid-IR frequency combs, QCL combs, QCLs in new regions of the mid-IR (λ beyond 15 µm)… (ii) novel ultra-fast detectors: quantum well infrared photodetectors (QWIPs), quantum cascade detectors (QCDs)… (iii) other mid-IR photonics devices such as novel amplitude or phase modulators. The successful applicant will in particular integrate ultra-sensitive and ultra-fast (frequency response of a few tens of GHz) quantum detectors based on a technology recently developed by LPENS, one of the partners of the CORALI project. She/he will characterize and optimize the performance (responsivity, detectivity, frequency response…) of these IR detectors, and aim to demonstrate unprecedented sensitivities using them in heterodyne detection systems. This will necessitate to use metrology-grade QCLs and set-up frequency metrology and ultra-high resolution spectroscopy demonstrators.

This project will significantly advance the field of frequency metrology, mid-IR photonics and cold molecule research. It opens possibilities for using polyatomic molecules and mid-IR technologies to perform tests of fundamental physics and probe the limits of the standard model, and to explore applications in astrophysics and atmospheric sciences, in order, for instance, to improve the current spectroscopic resolution limitations of LIDAR and heterodyne radiometry systems. The candidate will contribute to a leading-edge field, gaining expertise in state-of-the-art technologies and methodologies.

Skills

The applicant should have a PhD in a relevant area of experimental physics or chemical physics: molecular, atomic physics, spectroscopy, photonics, optics and lasers, quantum optics. She/he will be expected to display the initiative and creativity, together with the appropriate skills and knowledge, required to meet the project goals.

Work Context

The CORALI project funded by ANR is a collaboration between Laboratoire de physique de l'ENS (LPENS), Office National d'Etudes et Recherches Aérospatiales (ONERA), Laboratoire de Physique des Lasers (LPL) and THALES Research & Technology (TRT). The long-term goal is to provide sensitive, accurate and compact mid-IR detection systems for radiometry and LIDAR applications based on QCLs and QWIPs operating at room temperature. The activity will take place at LPL, Université Sorbonne Paris Nord, Villetaneuse, within the 'Metrology, Molecules and Fundamental Tests' team (MMFT), but the successful applicant will interact with the partners of the CORALI project, in particular with the LPENS partner, and will thus have a decisive role to maximise the synergy between them.

Constraints and risks

Not applicable.