Electric field effect control of a superconducting YBa2Cu3O7 inductor

Abstract

We discuss the design, fabrication, and testing of a thin‐film superconducting voltage‐controlled inductor which is made from a YBa₂Cu₃O₇ (YBCO) superconducting field effect transistor. Applying voltage to an Au gate layer alters the areal carrier density, and hence the kinetic inductance, of an underlying 100‐nm‐thick YBCO channel layer. The channel is connected in series with an input coil to form a closed superconducting 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 +2.6×10⁻⁴/V of applied gate voltage, close to the expected value.