Influence of electric fields on pinning in YBa_{2}Cu_{3}O_{7-δ} films

Experimental evidence is provided that the pinning force and the critical current density of ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_{7\mathrm{-}\mathrm{\delta }}$ films can be controlled by electric fields. This novel effect is attributed to field-induced changes of the density of mobile charge carriers in the superconductor.