| Přispěvatelé: |
SRF Editorial Committee, Pompeo, Nicola, Torokhtii, K, Alimenti, A, Silva, E, Celentano, G., Pinto, V., Rizzo, F., Spina, T., Flükiger, R., SRF2021, Alimenti, A., Torokhtii, K., Silva, E. |
| Popis: |
New potential rf applications of superconductors emerged with the need to operate in high dc magnetic fields (up to 16 T) where vortex motion dictates the response: the beam screen coating of the Future Circular Collider (FCC) and haloscopes, i.e. rf cavities for the axions detection. However, very few data are available in the required regimes. We present in this work measurements of the surface impedance Z up to 12 T on bulk Nb3Sn and YBCO thin films grown by different techniques. The measurements are performed with a dielectric loaded resonator operating at 15 GHz. We obtained the vortex motion resistivity and extracted the high frequency vortex motion parameters: the depinning frequency, the flux-flow resistivity and the pinning constant, as well as their temperature and field dependences. Substantial differences are highlighted in the high frequency pinning properties of the studied materials, providing useful information on possible improvements in view of applications. A comparison with the results obtained in the microwave frequency range at lower fields (up to 1 T) is given. |
