Observation of quantized circulation in superfluid B3

Abstract

We report the first observation of quantized circulation in superfluid B3. The apparatus consists of a straight vibrating wire immersed in liquid He3, which is cooled by a rotating nuclear demagnetization cryostat. The experiment is carried out at about 250 K. The superfluid at this temperature is in the ballistic quasiparticle regime. Circulation around the wire is found to be stable only when it takes on the values -h/2m3, 0, and +h/2m3, where h is Plancks constant and m3 is the mass of the He3 atom. This experiment confirms that superfluid B3 is a Cooper-paired superfluid with a macroscopic quantum wave function. Show more