Transistor characteristics in a three-terminal structure having YBa2Cu3O7−x electrodes on an insulating SrTiO3 substrate

Transistor characteristics in which both voltage and current gains exceeded one, were observed at 4.2 K in a three-terminal superconducting structure. A high critical-temperature superconducting YBa2Cu3O7−x emitter and collector were fabricated on a high-permittivity insulating SrTiO3 dielectric with a back-contact base electrode. The three-terminal structures were constructed on 500-μm-thick (100) single-crystal SrTiO3 substrates with a relative permittivity of 2×104 at 4.2 K. YBa2Cu3O7−x films were deposited on chemically cleaned substrates by laser ablation and base leads were constructed of silver paste.