Electric field effect on superconducting YBa₂Cu₃O_7-δ films

Experimental evidence for a significant electric field effect in thin superconducting films of YBa2Cu3O7-δ is presented. MISFET-type structures have been developed which allow the application of electric fields larger than 4×106 V/cm across insulating SrTiO3 barriers into thin cpitaxial YBa2Cu3O7-δ channel layers. The results demonstrate that with these structures the electrical resistivity above Tc (R=0) and the density of free carriers in the YBa2Cu3O7-δ films can be modified by 1-2% with gate voltages smaller than 50 V. © 1991 Springer-Verlag.