High Frequency Nonlinear Response of Superconducting Cavity-Grade Nb surfaces
arXiv:1904.07432 · doi:10.1103/PhysRevApplied.11.064030
Abstract
Nb Superconducting Radio-Frequency (SRF) cavities are observed to break down and lose their high-Q superconducting properties at accelerating gradients below the limits imposed by theory. The microscopic origins of SRF cavity breakdown are still a matter of some debate. To investigate these microscopic issues temperature and power dependent local third harmonic response was measured on bulk Nb and Nb thin film samples using a novel near-field magnetic microwave microscope between 2.9K-10K and 2GHz-6GHz. Both periodic and non-periodic response as a function of applied RF field amplitude are observed. We attribute these features to extrinsic and intrinsic nonlinear responses of the sample. The RF-current-biased Resistively Shunted Junction (RSJ) model can account for the periodic response and fits very well to the data using reasonable parameters. The non-periodic response is consistent with vortex semi-loops penetrating into the bulk of the sample once sufficiently high RF magnetic field is applied, and the data can be fit to a Time-Dependent Ginzburg-Landau (TDGL) model of this process. The fact that these responses are measured on a wide variety of Nb samples suggests that we have captured the generic nonlinear response of air-exposed Nb surfaces.
References in corpus (18)
- The Superconducting TESLA Cavities
- The Nonlinear Meissner Effect in Unconventional Superconductors
- Understanding Quality Factor Degradation in Superconducting Niobium Cavities at Low Microwave Field Amplitudes
- Dynamics of vortex penetration, jumpwise instabilities and nonlinear surface resistance of type-II superconductors in strong rf fields
- Tunneling study of cavity grade Nb: possible magnetic scattering at the surface
- Effect of Low Temperature Baking in Nitrogen on the Performance of a Niobium Superconducting Radio Frequency Cavity
- Doping-Dependent Nonlinear Meissner Effect and Spontaneous Currents in High-Tc Superconductors
- Microwave Nonlinearities of an Isolated Long YBa_2Cu_3O_(7-d) Bi-crystal Grain Boundary
- Phase-sensitive Harmonic Measurements of Microwave Nonlinearities in Cuprate Thin Films
- Nonlinear Near-Field Microwave Microscope For RF Defect Localization in Superconductors
- Nanoscale Nonlinear Radio Frequency Properties of Bulk Nb : Origins of Extrinsic Nonlinear Effects
- Nanoscale Electrodynamic Response of Nb Superconductors
- Near-Field Microwave Magnetic Nanoscopy of Superconducting Radio Frequency Cavity Materials
- Non-linear microwave impedance of short and long Josephson Junctions
- Observation of Individual Josephson Vortices in YBCO Bicrystal Grain-boundary Junctions
- A low energy muon spin rotation and point contact tunneling study of niobium films prepared for superconducting cavities
- Low frequency noise in ballistic Nb/Ag point contacts
- Nonlinear dynamics of Josephson vortices in a film screen under dc and ac magnetic fields
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- Microscopic Examination of SRF-quality Nb Films through Local Nonlinear Microwave Response
- Structured light and induced vorticity in superconductors I: Linearly polarized light
- Microwave Microscope Studies of Trapped Vortex Dynamics in Superconductors
- A Time-Dependent Ginzburg-Landau Framework for Sample-Specific Simulation of Superconductors for SRF Applications
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