Observing the drop of resistance in the flow of a superfluid Fermi gas
- 28 November 2012
- journal article
- Published by Springer Science and Business Media LLC in Nature
- Vol. 491 (7426), 736-739
- https://doi.org/10.1038/nature11613
Abstract
The ability of particles to flow with very low resistance is characteristic of superfluid and superconducting states, leading to their discovery in the past century. Although measuring the particle flow in liquid helium or superconducting materials is essential to identify superfluidity or superconductivity, no analogous measurement has been performed for superfluids based on ultracold Fermi gases. Here we report direct measurements of the conduction properties of strongly interacting fermions, observing the well-known drop in resistance that is associated with the onset of superfluidity. By varying the depth of the trapping potential in a narrow channel connecting two atomic reservoirs, we observed variations of the atomic current over several orders of magnitude. We related the intrinsic conduction properties to the thermodynamic functions in a model-independent way, by making use of high-resolution in situ imaging in combination with current measurements. Our results show that, as in solid-state systems, current and resistance measurements in quantum gases provide a sensitive probe with which to explore many-body physics. Our method is closely analogous to the operation of a solid-state field-effect transistor and could be applied as a probe for optical lattices and disordered systems, paving the way for modelling complex superconducting devices.Keywords
This publication has 31 references indexed in Scilit:
- High-resolution imaging of ultracold fermions in microscopically tailored optical potentialsNew Journal of Physics, 2011
- Viscosity and scale invariance in the unitary Fermi gasAnnals of Physics, 2011
- Exploring the thermodynamics of a universal Fermi gasNature, 2010
- Determination of the fermion pair size in a resonantly interacting superfluidNature, 2008
- Many-body physics with ultracold gasesReviews of Modern Physics, 2008
- Critical Velocity for Superfluid Flow across the BEC-BCS CrossoverPhysical Review Letters, 2007
- Crossover from a Molecular Bose-Einstein Condensate to a Degenerate Fermi GasPhysical Review Letters, 2004
- Observation of a Strongly Interacting Degenerate Fermi Gas of AtomsScience, 2002
- Interatomic collisions in a tightly confined Bose gasPhysical Review A, 2001
- Superfluid and Dissipative Dynamics of a Bose-Einstein Condensate in a Periodic Optical PotentialPhysical Review Letters, 2001