# AC Susceptibility Techniques Applied to Thin Film Superconductors

## Abstract

The techniques of ac susceptibility have been used to evaluate several properties of thin films: critical temperature, critical current density, and penetration depth. Two basic approaches have been used. The first I would call “conventional”, in that the sample is mounted in a conventional ac susceptibility apparatus that is normally used to measure bulk samples. Here the drive and receive coils are both large compared to the lateral dimensions of the sample. A second approach is unique to thin films and involves drive and receive coils that are small compared to the lateral dimensions of the sample. These coils are generally designed to couple only to a region near the center of the sample, thus being insensitive to the exact size or details of the outer edge of the film.

## Keywords

Mutual Inductance Mutual Coupling Total Magnetic Moment Total Moment Flux Creep## Preview

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## References

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