Superfluid Atomic Fermi Gas With a Vortex

Published

February 1, 2004

Author(s)

N Nygaard, G M. Bruun, B I. Schneider, D L. Feder, Charles W. Clark

Abstract

Dilute atomic gases have become a powerful tool for studying many-body quantum mechanics. The best example of this is the achievement of Bose-Einstein condensation in 1995 in a gas of Bose atoms, a discovery which has invoked a confluence of ideas from condensed matter, atomic and nuclear physics. Now a concerted research effort is focused on creating and studying a BCS (Bardin-Cooper-Schrieffer) superfluid of Cooper pairs in an atomic Fermi gas. An outstanding issue is the apparent lack of a smoking gun for superfluidity in a Fermi gas, since the bulk properties are essentially unaffected by the pairing. We propose to focus on the macroscopic coherence of the gas in the superfluid phase, in particular its ability to sustain quantized vortices. The creation and subsequent detection of such persistent topological features would provide an unambiguous signature of superfluidity in the system.In the work presented here we investigate the structure and thermodynamic properties of a singly quantized vortex line in a gas of superfluid fermionic atoms. By solving the Bogoliubov-de Gennes equations self-consistently we make the first quantitative determination of the critical rotation frequency for thermodynamic stability of the vortex state, and study the nature of the bound states in the vortex core. These excitations fill the core, making direct imaging of the vortex unlikely. Instead, we propose an experiment to indirectly probe the supercurrent associated with the vortex state with laser fields, in a scheme analogous to Scanning Tunneling Microscopy. Furthermore, it is shown that the vortex state causes a shift of the superfluid transition temperature, which can be understood as a finite size effect.

Proceedings Title

Sigma Xi Postdoctoral Poster Presentations, 2004

Conference Dates

February 19-20, 2004

Conference Location

Undefined

Pub Type

Conferences

Keywords

atomic, fermi, gas, superfluid, vortex

Citation

Nygaard, N. , Bruun, G. , Schneider, B. , Feder, D. and Clark, C. (2004), Superfluid Atomic Fermi Gas With a Vortex, Sigma Xi Postdoctoral Poster Presentations, 2004, Undefined (Accessed July 17, 2024)