Superconducting characteristics of a planar-type HoBa2Cu3O7−<i>x</i> −La1.5Ba1.5Cu3O7−<i>y</i>−HoBa2Cu3O7−<i>x</i> junction

Abstract

A planar-type junction of HoBa2Cu3O7−x−La1.5Ba1.5Cu3O7−y −HoBa2Cu3O7−x having an electrode spacing as small as 0.1 μm is fabricated and its electrical characteristics are measured. Supercurrent through the La1.5Ba1.5Cu3O7−y layer is detected up to the temperature of 69 K. A superconducting region extends from the YBa2Cu3O7−x electrodes into a normal La1.5Ba1.5Cu3O7−y layer with a submicrometer scale. The superconducting decay length is 65 nm, which is two orders of magnitude larger than the value calculated from the conventional proximity theory.