News and Events
Optical measurement of the equation of state of bulk liquid helium-4 around 1 K, L. Djadaojee, J. Grücker, Phys. Rev. B 103, 144513 (2021) [5 pages]
Stimulated Brillouin gain spectroscopy in a confined spatio-temporal domain (30 μm, 170 ns) L. Djadaojee, A. Douillet, J. Grücker, Eur. Phys. J. Appl. Phys. 89, 30701 (2020) [5 pages] Open access
Nuclear hyperpolarization of ³He by magnetized plasmas, Maul A., Blümler P., Nacher P.-J., Otten E., Tastevin G., and Heil W., Phys. Rev. A (2018) 98, 063405 [12 pages]
Doppler-free spectroscopy of the lowest triplet states of helium using double optical resonance, A. Dia, M. Abboud, P.-J. Nacher, and G. Tastevin – Eur. Phys. J. D (2021) 75:223 – SharedIt link
Ali DIA gradutated from ENS-PSL (Paris) and USJ (Beyrouth) on May 7, 2021.
Experimental study of redistribution and exchange collisions in the 2³P level of helium
Lionel DJADAOJEE (Teaching assistant at ENS Paris – PSL, Agrégé de Physique) has joined the group for PhD work on the metastable phases of solid and liquid 4He (J. Grücker, superviser; Sept. 2019 – …).
Philippe Jacquier, leader of the “Quantum solid and liquid helium” team since 2003, passed away on Jan.24, 2019.
Hyperpolarisation of ³He nuclear spin at moderate/high magnetic field
M2 internship work: Unveiling the mechanism for nuclear spin self-orientation in ³He gas discharges.
Type of work: Instrumental, experimental.
Context and objectives: Read a 1-page summary - Visit our website - Contact us.
Opening for PhD: Come and join the team for a 3-year contribution to the HELPING project focused on the control of ³He nuclear spin state in magnetised rf gas discharges!
This project provides a unique opportunity for basic and applied research work, as well as for training in a variety of techniques such as laser spectroscopy, optical polarimetry, NMR measurements and imaging, cryogenics, to name a few.
More about recruitment
Low field MRI - Polarised helium-3
Skilled and motivated students are welcome to join our investigations on low field MRI with laser-polarised ³He gas or thermally-polarised water samples. Work may focus on the impact of concomitant field gradients on image quality, or investigate the short-pulse limit and revisit the Bloch-Siegert effect in pulsed NMR. This topic is open for PhD.
Measurements of magnetic field strengths in a low-field MRI system
Mesures de champs magnétiques dans un système pour l’IRM à bas champ
Objective: Use and comparison of different methods allowing measurement of the magnetic field strengh.
Context: Magnetic resonance imaging typically involves a static (main) field, pulsed (imaging) field gradients, and oscillatory (rf) fields. For low field operation, various types of devices or magnetic sensors may be used for accurate control of, both, applied and stray fields.
Work: Physical measurements, data acquistion (output voltages). MRI tests, data analysis, correlation with image features.
MAgnetic Resonance studies of Gas diffusion In Nanoporous materials (MARGIN)
Context: Collaborative research project involving the Laboratoire Kastler Brossel (ENS-PSL, Paris) and the MRS Lab (Kazan Fed. Univ., Kazan, Russian Federation).
Objective: Investigations of gas diffusion in nano-scale void spaces at low and high temperature. Assessment of the influence of the attractive wall potential on molecular gas dynamics, so far overlooked in standard diffusion models.
Work : Use ³He as a probe gas and measure the apparent diffusion coefficient at room temperature in different porous systems, such as ordered aerogels, nanopowders, etc. Perform NMR and MRI experiments at low field (mT), using hyperpolarisation by laser optical pumping for high detection sensitivity. Make numerical simulations of restricted gas diffusion for reliable interpretation of the experimental findings.
Funding of the project: Joint ANR-RSF grant.
Location: LKB, Department of Physics of ENS, 24 rue Lhomond, 75005 Paris, France
Duration: 18 to 24 months, depending on the applicant's qualifications
Polarised helium - Liquid NMR
Skilled and motivated students are welcome to join the team for follow-up of our investigations on liquid NMR in laser polarised ³He-⁴He dilute solutions. Work will deal with the latest observations of non linear NMR dynamics and will focus on the comparison between experimental and numerical data. This topic is not open for PhD this year.
We are always looking for brillant motivated scientists to join our group.
Check the open positions (see above) or send us your CV for application.
Département de Physique Ecole Normale Supérieure, 24 rue Lhomond, F-75231 Paris Cedex 05
- Jules Grucker : jules.grucker at lkb.ens.fr
- Franck Laloë : laloe at lkb.ens.fr
- Pierre-Jean Nacher : nacher at lkb.ens.fr
- Geneviève Tastevin : genevieve.tastevin at lkb.ens.fr