Observation of Phase Slips in Spin Supercurrents in 3 He–B

We have observed spin supercurrents which transport the longitudinal magnetization of 3 He–B through a narrow channel connecting two chambers filled with superfluid 3 He–B. The magnetization of 3 He–B in these chambers and in the channel is tilted by the angle 104° and processes. The magnitude of the spin supercurrent is determined by the difference in the precession phase angle between the ends of the channel. The critical supercurrent is measured when phase slips take place.