Ice Particles in the Superfluid Flow

A close-up photograph of tiny, white solidified hydrogen tracer particles suspended in liquid. The particles are scattered throughout the frame, some appearing as distinct dots while others form thin, wispy lines and clusters, visualizing the "invisible" flow of superfluid helium by becoming trapped in its vortices

Label: Ice Particles in the Superfluid Flow
Artist: Toshiaki Kanai
Description: These are tiny solidified hydrogen particles used to make the flow of superfluid helium visible. When liquid helium is cooled below a critical temperature of around -450.20° Fahrenheit (2.17 Kelvin), it becomes a superfluid with zero viscosity. In regular fluids, tracer particles are carried along by viscous forces to visualize flows, but this method does not work in superfluid helium due to zero viscosity. Instead, the particles become trapped by vortices (i.e., tiny whirlpools), allowing researchers to observe the “invisible” flow. The original video was created September 2022. This picture was clipped March 2023.
Type: High-speed Camera
Artist Affiliation: Graduate Student
Department: Physics
Area of Research: Low-temperature Physics
Research Group Site: National High Magnetic Field Laboratory Cryogenics Group
Date: 2023