A superfluid boundary layer
نویسندگان
چکیده
We model the superfluid flow of liquid helium over a real surface, derived from a wire used to experimentally generate turbulence (profiled by atomic force microscopy). We employ large-scale, microscopically-resolved numerical simulations of the Gross-Pitaevskii equation to find that vortices nucleate predominantly from the sharpest features in the surface, and drive the formation of a complex boundary layer of vortex loops and rings. As boundary layers conventionally arise from viscous forces, this result is surprising and opens up new insight into the nature of superflows at real boundaries.
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