Continuous reel-to-reel measurement of critical currents of coated conductors

We demonstrate that magnetization measurements by Hall probe arrays are well suited for the reel-to-reel determination of critical currents along long lengths of coated conductors. The technique is contact-free, fast, simple, and it has a high spatial resolution. A quantitative measure of the critical current as a function of position was obtained by fitting a simple critical state model to the field distribution. The technique is demonstrated for YBa2Cu3O7 films on single-crystal substrates and then applied to samples of coated conductors.