Computational Modelling Group

Seminar  20th November 2012 noon  54/8033

Highly polarized limit of the quasi-2D Fermi gas

Jesper Levinsen
Cambridge

Web page
http://www.wolfson.cam.ac.uk/people/dr-jesper-levinson
Categories
Complex Systems
Submitter
Luke Goater

Highly polarized limit of the quasi-2D Fermi gas

An ultracold gas of fermionic atoms with short range interactions represents a unique playground for studying pairing and effective interactions in a strongly correlated system due to the fine control of dimensionality and interactions. In this talk, I will start by reviewing recent theoretical and experimental progress in the field. Focussing next on the highly polarized limit of the quasi-2D Fermi gas, I will discuss properties of the quasiparticles which a single impurity can form when immersed in a Fermi sea. I will show how the ground state transition of the attractive branch is shifted by the quasi-2D confinement and how this can be described quantitatively throughout the 2D to 3D crossover. I will also demonstrate how the fast decay of the repulsive branch precludes itinerant ferromagnetism in this system.

References

“Highly polarized limit of the quasi-two-dimensional Fermi gas”, J. Levinsen and S. K. Baur, arXiv:1202.6564 “Repulsive polarons in two-dimensional Fermi gases”, V. Ngampruetikorn, J. Levinsen, and M. M. Parish, EPL 98, 30005 (2012)