Flow of Helium-4 in One-dimensional Channel*

Superfluidity breaks down in the one-dimensional limit. However, other experiments have demonstrated superfluid flow through pores on the order of nanometers. Here we report on studying liquid helium flow through a single-hole glass capillary with internal diameters ranging from 80 to 150 nm. We observed a significant flow rate increase below the lambda transition temperature. The estimated critical velocities at low temperatures are approximately 10 m/s, which belongs to the highest group of measured critical velocities.