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Full-Text Articles in Physics
Magnetic Field Sensors For Detection Of Trapped Flux In Superconducting Radio Frequency Cavities, Ishwari Prasad Parajuli, Gianluigi Ciovati, Jean R. Delayen
Magnetic Field Sensors For Detection Of Trapped Flux In Superconducting Radio Frequency Cavities, Ishwari Prasad Parajuli, Gianluigi Ciovati, Jean R. Delayen
Physics Faculty Publications
Superconducting radio frequency (SRF) cavities are fundamental building blocks of modern particle accelerators. They operate at liquid helium temperatures (2–4 K) to achieve very high quality factors (1010–1011). Trapping of magnetic flux within the superconductor is a significant contribution to the residual RF losses, which limit the achievable quality factor. Suitable diagnostic tools are in high demand to understand the mechanisms of flux trapping in technical superconductors, and the fundamental components of such diagnostic tools are magnetic field sensors. We have studied the performance of commercially available Hall probes, anisotropic magnetoresistive sensors, and flux-gate magnetometers with …
Dynamic Pair-Breaking Current, Critical Superfluid Velocity, And Nonlinear Electromagnetic Response Of Nonequilibrium Superconductors, Ahmad Sheikhzada, Alex Gurevich
Dynamic Pair-Breaking Current, Critical Superfluid Velocity, And Nonlinear Electromagnetic Response Of Nonequilibrium Superconductors, Ahmad Sheikhzada, Alex Gurevich
Physics Faculty Publications
We report numerical calculations of a dynamic pair-breaking current density Jd and a critical superfluid velocity vd in a nonequilibrium superconductor carrying a uniform, large-amplitude AC current density J(t)=JasinΩt with Ω well below the gap frequency Ω ≪ Δ0/h. The dependencies Jd(Ω,T) and vd(Ω,T) near the critical temperature Tcwere calculated from either the full time-dependent nonequilibrium equations for a dirty s-wave superconductor or the time-dependent Ginzburg-Landau (TDGL) equations for a gapped superconductor, taking into account the GL relaxation time of the order parameter GL …