Abstract. The authors have observed experimentally the analog of the superfluid helium fountain effect in a polycrystalline YBaCuO film. In a superconductor a temperature gradient induces the counterflow of superconducting electrons and quasiparticles. The supercurrent creates a phase difference at the intra- and intergrain weak links. In the presence of a temperature gradient parallel to an electric current they have detected an asymmetry of the current-voltage characteristic. Reversing the direction of the temperature gradient also reverses the sign of the current asymmetry. They estimate the thermoelectric coefficient for the quasiparticles in the YBaCuO sample.

Print publication: Issue 1S (January 1991)