Abstract
Abstract
The two-coil mutual inductance (TCMI) technique is a useful experimental method to derive the magnetic penetration depth λ in a superconducting film after proper numerical calculations, in which various film geometries including infinite, circular and quadrangle films have been utilized. Based on previously reported reflection-type TCMI experimental data taken from NbN and K-adsorbed FeSe thin films, we investigate the validity of various numerical models with different geometries by comparing their calculation results. The calculated values of λ for various film geometries become identical only when the film size is at least three times larger than the coil size. For a rectangular film with a width comparable to the coil size, the numerical models of circular and square film geometries with proper sizes can also be adopted to obtain a similar λ value as that calculated with a rectangular film geometry. Although the true value of λ can be approximately achieved only after a complicated calibration, its calculated temperature dependence is insensitive to the choice of numerical models. With these results, a proper film geometry for the numerical calculation of λ may be selected to effectively improve the calculation efficiency.
Funder
Science and Technology Commission of Shanghai Municipality
Strategic Priority Research Program of Chinese Academy of Sciences
Ministry of Science and Technology of China
National Natural Science Foundation of China
Subject
Materials Chemistry,Electrical and Electronic Engineering,Metals and Alloys,Condensed Matter Physics,Ceramics and Composites