Tunneling transport of atomic Fermi gases across the superfluid phase transition

In this article, I review on two recent experiments on tunneling transport of atomic Fermi superfluids. By injecting controlled currents in a two-reservoir system coupled through a thin barrier, Josephson critical currents are directly accessed and employed to extract the condensed fraction of strongly interacting fermionic superfluids. At finite temperature, Josephson supercurrents are observed to breakdown when approaching the critical temperature of the superfluid phase transition, thus demonstrating them as a reliable probe of condensation at any temperature. Furthermore, the study of resistive currents reveals the importance of Bogoliubov-Anderson sound modes in the conduction of a unitary gas, increased by the phonon-condensate coupling at low temperature. These works highlight how transport measurements can unveil both the coherence properties and the role of excitations in quantum matter.