Experimental Observation of a Self-Heating Effect of Helium-4 Superflow

Abstract

we report a counter-intuitive self-heating effect of 4 He superflow. This fundamentally unusual heating effect bears a phenomenological resemblance to the Peltier effect of electric current across two different conductors. It reveals that 4 He superflow carries thermal energy and entropy, which is in contrast to the two-fluid model of superfluid 4 He. A natural understanding of this heating effect is provided by a recently developed microscopic quantum theory of superfluid 4 He.