Nitrogen doping and infusion in SRF cavities: A review

P Dhakal - Physics Open, 2020 - Elsevier
Advances in SRF technology over the last 40 years allowed achieving accelerating
gradients~ 50​ MV/m corresponding to peak surface magnetic fields close to the theoretical …

Characterization of dissipative regions of a N-doped superconducting radio-frequency cavity

EM Lechner, BD Oli, J Makita, G Ciovati… - Frontiers in Electronic …, 2023 - frontiersin.org
We report radio-frequency measurements of quality factors and temperature mapping of a
nitrogen doped Nb superconducting RF cavity. Cavity cutouts of hot and cold spots were …

Accelerating gradient improvement in nitrogen-doped superconducting radio-frequency cavities for SHINE

Y Zong, JF Chen, D Wang, QX Chen, ZX Chen… - Nuclear Instruments and …, 2023 - Elsevier
Several state-of-the-art recipes have been studied to pursue high quality factor (Q) and
higher accelerating gradient (E acc) on superconducting radio-frequency (SRF) cavities for …

Surface characterization of nitrogen-doped high purity niobium coupons compared with superconducting rf cavity performance

P Dhakal, G Ciovati, U Pudasaini, S Chetri… - … Review Accelerators and …, 2019 - APS
We report the results from the measurements of high purity Nb samples and
superconducting radio-frequency (SRF) cavities doped with nitrogen and followed by either …

[PDF][PDF] Challenges to Reliable Production Nitrogen Doping of Nb for SRF Accelerating Cavities

C Reece, J Angle, M Kelley, E Lechner… - … Conference (IPAC'22) …, 2022 - inspirehep.net
Over the last several years, alloying of the surface layer of niobium SRF cavities has been
demonstrated to beneficially lower the superconducting RF surface resistance. Nitrogen …

[PDF][PDF] Vacancy-Hydrogen Dynamics and Magnetic Impurities During Mid-T Bake

M Wenskat, C Bate, GDL Semione, A Stierle… - … edited by K. Saito, T. Xu …, 2021 - jacow.org
Positron annihilation measurements allow to study the hydrogen interaction with vacancies
in a crystal lattice. Furthermore, the 3𝛾/2𝛾 ratio of the positronium annihilation showed local …

[PDF][PDF] A SIMS Approach for the Analysis of Furnace Contamination

J Angle, E Lechner, AD Palczewski… - … Conference on RF …, 2022 - accelconf.web.cern.ch
Detection of surface contamination for SRF material is difficult due to the miniscule quantities
and near atomic resolution needed. Visual inspection of samples known to have …

Electropolishing study on nitrogen-doped niobium surface

V Chouhan, T Ring, E Viklund, G Wu - 2023 - osti.gov
The nitrogen doping (N-doping) process is applied to niobium (Nb) superconducting cavities
to enhance their quality factors. The N-doping is followed by an electropolishing process that …

Topographic Evolution of Nb Surfaces Subjected to Electropolishing

EM Lechner, CG Baxley, MJ Kelley, CE Reece… - 2023 - osti.gov
Surface quality plays an important role in the performance of SRF cavities. We report the
topographic evolution of H degassed, N and O doped Nb surfaces subjected to …

Topographic Evolution of Nitrogen Doped Nb Subjected to Electropolishing

E Lechner, J Angle, C Baxley, M Kelley, C Reece - 2023 - osti.gov
Surface quality is paramount in facilitating high per-formance SRF cavity operation. Here we
investigate the topographic evolution of samples subjected to N doping and 600° C vacuum …