| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1817894 | Physica C: Superconductivity and its Applications | 2013 | 6 Pages |
•SRF accelerator cavity performance (quality factor Qo) is controlled by surface impedance.•A field-dependent derivation of the Mattis–Bardeen theory of SRF surface impedance is presented.•The complete range of gradients is treated for the first time.•Agreement with experiment is excellent.
Based on BCS theory with moving Cooper pairs, the electron states distribution at 0 K and the probability of electron occupation with finite temperature have been derived and applied to anomalous skin effect theory to obtain the surface impedance of a superconductor under radiofrequency (RF) field. We present the numerical results for Nb and compare these with representative RF field-dependent effective surface resistance measurements from a 1.5 GHz resonant structure.
