STAGE Frequency-doubling of a picosecond frequency-comb laser for atom interferometry

Date de mise à jour de l’offre

Centre national de la recherche scientifique (CNRS) IDF Villejuif :

Le Centre national de la recherche scientifique est un organisme public de recherche pluridisciplinaire placé sous la tutelle du ministère de l’Enseignement supérieur, de la Recherche et de l’Innovation. Missions : faire de la recherche scientifique, valoriser les résultats, partager les connaissances, former par la recherche, contribuer à la politique scientifique.

Description de la mission

Light-pulse atom interferometry, where light pulses are used as atom beam splitters, has led to extremely sensitive and accurate quantum sensors that can be used to perform very stringent tests of fundamental physics such as: testing the equivalence principle, detecting gravitational waves, probing short-range forces or measuring fundamental constants (e.g. Newton’s gravitational constant or the fine-structure constant). Until recently, light-pulse atom interferometry had only exploited continuous-wave (cw) laser sources. We have recently demonstrated atom interferometers where the beam splitters are realized with pulsed lasers, or more specifically frequency-comb lasers [1]. This major achievement, which we obtained in the visible spectrum on rubidium (Rb) atoms, paves the way for extending light-pulse interferometry to other wavelengths (e.g. deep-UV to X-UV) and therefore to new species, since one can benefit from the high peak intensity of the ultrashort pulses which makes frequency conversion in nonlinear media efficient.
Our team is currently working along two lines of research which aim at: 1) pushing the limits of frequency-comb-driven atom interferometry (FCAI) and 2) extending FCAI to other wavelengths. In particular, we are currently designing and building a new experimental setup to cool and trap ytterbium (Yb) atoms, and perform FCAI on their 6s2 1S0 6s6p 1P1 transition around 399 nm.

Profil recherché

Master thesis work, research activities:
This work will focus on the frequency-doubling of a picosecond frequency-comb laser at 798 nm. The generated comb at 399 nm will be used to perform frequency-comb atom interferometry (FCAI) on the 6s2 1S0 6s6p 1P1 transition of Ytterbium atoms. This involves:
- the design and implementation of the optical setup for second harmonic generation
- characterization of the generated comb at 399 nm (power stability, frequency stability, …)
- locking the central wavelength of the comb
- setting up the optical beam-path, including an acousto-optic modulator (AOM), motorized translation stage, …
- state manipulation of Rb atoms (or Yb atoms depending on the advancement of the Yb project) with the generated frequency comb

Skills gained:
- Experience with optics incl. frequency-doubling in non-linear crystals, …
- Experience with frequency-comb lasers
- Quantum state manipulation of atoms
- Experience with electronics, servo-loop...

Niveau de qualification requis

Bac + 4/5 et +
  • Employeur
    Centre national de la recherche scientifique (CNRS) IDF Villejuif
  • Secteur d’activité de la structure
    Enseignement - Formation - Recherche
  • Effectif de la structure
    Plus de 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 2 mois et jusqu'à 4 mois
  • Le stage est-il rémunéré ?
    Oui
  • Niveau de qualification requis

    Bac + 4/5 et +
  • Lieu du stage
    Laboratoire Kastler Brossel Sorbonne Université
    4, place de Jussieu
    75005 PARIS 5E ARRONDISSEMENT
  • Accès et transports
    RATP, Bus (https://www.ratp.fr/), SNCF (https://www.sncf.com/fr)