Depth-resolved measurements of the Meissner screening profile in surface-treated Nb

Abstract

We report depth-resolved measurements of the Meissner screening profile in several surface-treated Nb samples using low-energy muon spin rotation (LE-$\mu$SR). In these experiments, implanted positive muons, whose stopping depths below Nb's surface were adjusted between ~10 nm to ~150 nm, reveal the field distribution inside the superconducting element via their spin-precession (communicated through their radioactive decay products). We compare how the field screening is modified by different surface treatments commonly employed to prepare superconducting radio frequency (SRF) cavities used in accelerator beamlines. In contrast to an earlier report [A. Romanenko et al., Appl. Phys. Lett. 104 072601 (2014)], we find no evidence for any "anomalous" modifications to the Meissner profiles, with all data being well-described by a London model. Differences in screening properties between surface treatments can be explained by changes to the carrier mean-free-paths resulting from dopant profiles near the material's surface.

arXiv comment15 pages, 5 figures, 2 tables

References in corpus (33)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Electron-phonon interactions and related physical properties of metals from linear-response theory
• musrfit: A free platform-independent framework for muSR data analysis
• Nitrogen and argon doping of niobium for superconducting radio frequency cavities: a pathway to highly efficient accelerating structures
• Effective Demagnetization Factors of Diamagnetic Samples of Various Shapes
• Assembling the puzzle of superconducting elements: A Review
• Unprecedented Quality Factors at Accelerating Gradients up to 45 MV/m in Niobium Superconducting Resonators via Low Temperature Nitrogen Infusion
• Intrinsic Paramagnetic Meissner Effect due to s-wave Odd-Frequency Superconductivity
• Superheating field of superconductors within Ginzburg-Landau theory
• Surface Superconductivity in Niobium for Superconducting RF Cavities
• Multilayer coating for higher accelerating fields in superconducting radio-frequency cavities: a review of theoretical aspects
• Radio-frequency electromagnetic field and vortex penetration in multilayered superconductors
• Remotely induced magnetism in a normal metal using a superconducting spin-valve
• Proximity-Induced Odd-Frequency Superconductivity in a Topological Insulator
• Observation of non-exponential magnetic penetration profiles in the Meissner state - A manifestation of non-local effects in superconductors
• Effect of interstitial impurities on the field dependent microwave surface resistance of niobium
• Strong Meissner screening change in superconducting radio frequency cavities due to mild baking
• Direct observation of non-local effects in a superconductor
• Superconductors in realistic geometries: Geometric edge barrier versus pinning
• The Effect of Inhomogeneous Surface Disorder on the Superheating Field of Superconducting RF Cavities
• Niobium in clean limit: an intrinsic type-I superconductor
• Field of first flux entry and pinning strength of superconductors for RF application measured with muon spin rotation
• Unconventional Meissner screening induced by chiral molecules in a conventional superconductor
• Geant4 simulation of the PSI LEM beam line: energy loss and muonium formation in thin foils and the impact of unmoderated muons on the $\mu$SR spectrometer
• High-Field Q-slope Mitigation due to Impurity Profile in Superconducting Radio-Frequency Cavities
• Superheating in coated niobium
• A New High Parallel-Field Spectrometer at TRIUMF's $\beta$-NMR Facility
• A low energy muon spin rotation and point contact tunneling study of niobium films prepared for superconducting cavities
• Modifications of the Meissner screening profile in YBa${}_2$Cu${}_3$O${}_{7-\delta }$ thin films by gold nanoparticles
• Evidence for Cooper Pair Diffraction on the Vortex Lattice of Superconducting Niobium
• Magnetic field distribution and characteristic fields of the vortex lattice for a clean superconducting niobium sample in an external field applied along a three-fold axis
• The magnetic penetration depth influenced by the proximity to the surface
• RF surface resistance tuning of superconducting niobium via thermal diffusion of native oxide

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• Depth-resolved measurement of the Meissner screening profile in a niobium thin film from spin-lattice relaxation of the implanted $\beta$-emitter ${}^8$Li
• Depth-resolved Characterization of Meissner Screening Breakdown in Surface Treated Niobium
• Search for inhomogeneous Meissner screening in Nb induced by low-temperature surface treatments
• Niobium's intrinsic coherence length and penetration depth revisited using low-energy muon spin spectroscopy and secondary-ion mass spectrometry
• Implantation studies of low-energy positive muons in niobium thin films
• Electropolishing-Induced Topographic Defects in Niobium: Insights and Implications for Superconducting Radio Frequency Applications