Dynamics of a Tunable Superfluid Junction. L. LeBlanc, A. Bardon, J. McKeever, M. Extavour, D. Jervis, J. Thywissen, F. Piazza and A. Smerzi in Phys. Rev. Lett. 106:025302 (2011).  What the paper says!?

This studies the crossover from hydrodynamic to Josephson regime for two condensates separated by a barrier:

we study the transport of a Bose-Einstein condensate (BEC) between two wells separated by a tun- able barrier and observe the crossover from hydrodynamic

to Josephson transport.

This makes, according to the Authors,

the first direct observation of tunneling transport of neutral atoms through a magnetic barrier,

only inferred [previously]

I don't find the paper extremely clear. They do not define what criterion exactly separates the two, except that the observed frequency of oscillations better matches a GPE treatment or a Josephson model.

This provides support to Nina Voronova et al. polaritonic Junction.