STAGE Widely tunable ultra-stable and SI-traceable quantum cascade lasers for frequency metrology and midinfrared precise spectroscopy: application to space, atmospheric and fundamental physics

Date de mise à jour de l’offre

Laboratoire de Physique des Lasers :

Le Laboratoire de Physique des Lasers étudie les interactions entre la lumière et la matière. Certaines de nos expériences sont très fondamentales, et d’autres appliquées. Nous étudions la physique quantique, la physique atomique et moléculaire, des systèmes optiques, l’optique biomédicale. Avec des lasers, nous étudions les propriétés quantiques de gaz à très basse température ; nous sondons les propriétés d’atomes ou de molécules au voisinage de surfaces ou de nano-objets ; nous faisons des expériences de spectroscopie moléculaire en utilisant des molécules toujours plus complexes (certaines sont d’intérêt biologique) ; nous faisons des mesures dans des milieux diffusants, ou même dans le corps humain.

Description de la mission

Ultra-high spectral resolution molecular spectroscopy is an interdisciplinary field with fascinating and far-reaching
applications ranging from fundamental physics to astrophysics, earth sciences, remote sensing, metrology and
quantum technologies. Among recent instrumental advances, the stabilization of quantum cascade lasers (QCLs) on
commercial optical frequency combs with traceability to primary frequency standards, a method recently
implemented in our team, is a breakthrough technology. It offers an unprecedented level of precision and resolution
in the mid-infrared, an essential region known as the molecular fingerprint region, which hosts a considerable number
of intense vibrational signatures of molecules of various interests. While the need for ultimate frequency control is
obvious for fundamental applications such as testing fundamental symmetries or measuring fundamental constants
and their possible variations, other fields such as atmospheric monitoring have surprisingly the same requirement.
Molecular remote sensing measurements are often limited by the quality of spectroscopic data, resulting from the
limited resolution of traditional spectrometers. The limited accuracy obtained for parameters affecting the line profile,
such as frequency shifts and widths, leads to systematic biases in the determination of atmospheric species
abundances, which is a crucial information for environmental and human health issues.
The techniques developed at the Laboratoire de Physique des Lasers can be used to overcome this type of bottlenecks.
For example, we have recently improved by 3 order of magnitude the accuracy on some methanol rovibrational line
centres compared to previous measurements reported in the literature. We are now adding a Fabry-Perot cavity to
our spectrometer to perform cavity enhanced spectroscopy which will allow us to target more complex molecules of
atmospheric, astrophysics and fundamental interest, and to improve our current spectroscopic resolution. During the
internship, the student will continue this work. She/ will:
- improve and characterise the spectroscopic properties of the apparatus;
- perform measurements on relatively complex molecular systems of interest for atmospheric sciences (CH3SCH3),
astrophysics (C3H6O3), and for probing the violation of fundamental symmetries (chiral organo-metallic species).

Profil recherché

The applicant should be doing its master studies in a relevant area of experimental physics or chemical physics:
atomic, molecular and optical physics, spectroscopy, 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.
Interested applicants should email a CV, a brief description of research interests and the contact details of 2 referents
to M. Manceau (mathieu.manceau@univ-paris13.fr) and/or B. Darquié (benoit.darquie@univ-paris13.fr).

Niveau de qualification requis

Bac + 4/5 et +
  • Employeur
    Laboratoire de Physique des Lasers
  • Secteur d’activité de la structure
    Enseignement - Formation - Recherche
  • Effectif de la structure
    De 51 à 250 salariés
  • Type de stage ou contrat
    Stage pour lycéens et étudiants en formation initiale
  • Date prévisionnelle de démarrage
  • Durée du stage ou contrat
    Plus de 4 mois et jusqu'à 6 mois
  • Le stage est-il rémunéré ?
    Oui
  • Niveau de qualification requis

    Bac + 4/5 et +
  • Lieu du stage
    The applicant should be doing its master studies in a relevant area of experimental physics or chemical physics: atomic, molecular and optical physics, spectroscopy, lasers, quantum optics. She/he will be expected to display the initiative and creativity,
    93430 VILLETANEUSE
  • Accès et transports
    http://www-lpl.univ-paris13.fr/FR/Venir-au-LPL.awp