ELECTRIC-FIELD EFFECT CONTROL OF A SUPERCONDUCTING YBA2CU3O7 INDUCTOR

We discuss the design, fabrication, and testing of a thin-film superco nducting voltage-controlled inductor which is made from a YBa2Cu3O7 (Y BCO) superconducting field effect transistor. Applying voltage to an A u gate layer alters the areal carrier density, and hence the kinetic i nductance, of an underlying 100-nm-thick YBCO channel layer. The chann el is connected in series with an input coil to form a closed supercon ducting loop. We use a dc superconducting quantum interference device at 4.2 -K to measure changes in loop inductance and find a fractional change in the kinetic inductance of about +2.6 X 10(-4)/V of applied g ate voltage, close to the expected value.