Predicting nonlinear effects in superconducting microwave transmission lines from mutual inductance measurements

摘要

We demonstrate the use of a new experimentaltechnique based on mutual inductance measurements toquantitatively predict nonlinear effects in microwave devicesfabricated from high-temperature superconductor (HTS) materials.The mutual inductance measurements yield the current dependenceof the penetration depth #gamma#(J) in unpatterned HTS thinfilms. This information is used to calculate third-harmonicgeneration in coplanar waveguide (CPW) transmission lines andcompares very well with actual measurements of CPWtransmission lines of variable dimensions fabricated fromYba_2Cu_3O_(7-#delta#) thin film samples. The mutualinductance measurements should prove extremely valuable as ascreening technique for microwave applications of HTS materialsthat require very low nonlinear response.