PhD in quantum gases (M/F)

Job Description

Thesis Subject

The aim of the PhD project is to study soliton gases using a one-dimensional degenerate quantum gas. For repulsive interactions between atoms, a soliton corresponds to a local depletion of density that propagates without dispersion within the gas. From the perspective of the atoms' wave function, a phase jump also occurs on the scale of the soliton's size. The gas under study will be trapped in a box-shaped magneto-optical potential. To excite the solitons, a linear perturbation of the trap with amplitude modulated over time will be applied. Depending on the duration and amplitude of the excitation, the soliton density can transition from a dilute regime, where solitons can be considered independently of one another, to a dense regime, where the system can be considered turbulent. The soliton gas will be studied after a flight time in order to determine the gas's momentum distribution. The project is primarily experimental but may include a component involving numerical simulations of these dynamics.

Your Work Environment

The activity will take place at Laboratoire de Physique des Lasers, a joint research unit of Université Sorbonne Paris Nord and CNRS. The Bose-Einstein Condensate group (BEC group, see https://bec.lpl.univ-paris13.fr/ ) has developed two experiments on the dynamics of quantum gases. The experiment on which the project will be based routinely produces a sodium quantum gas confined in a highly anisotropic harmonic potential. At low temperatures and for gases of a few thousand atoms, the system enters the one-dimensional regime, the energy scale of transverse excitations being higher than the characteristic energies of the gas.

The thesis will be directed by Hélène Perrin (DR CNRS) and co-supervised by Aurélien Perrin (CR CNRS). A lecturer, a post-doc and a PhD student will also be involved in the project, which is funded by the France 2030 program, PEPR project Dyn1D (Dynamics out of ́equilibrium of one-dimensional quantum gases), in collaboration with 10 other research groups mixing theoreticians and experimentalists. In addition, the BEC group includes another lecturer, a research engineer, two PhD students and a post-doc, mainly involved on the other experimental set-up. The group is part of the laboratory's Quantum Gases axis, which brings together some twenty researchers. In addition to those already mentioned in the context of this project, the BEC team has forged collaborations with several experimental and theoretical groups, including Anna Minguzzi at the LPMMC in Grenoble, Patrizia Vignolo and Sergey Nazarenko at the Institut de Physique in Nice, Maxim Olshanii at the University of Massachusetts in Boston, and Thorsten Schumm at the TUW University in Vienna.

Constraints and risks

Class IV laser: safety goggles must be worn. Electrical hazards: use of high voltage.

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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