[1] Grassellino A, Romanenko A, Posen S, et al. N doping: progress in development and understanding[C]//The 17th International Conference on RF Superconductivity. 2015: 48-54.
[2] Merio M, Checchin M, Crawford A, et al. Furnace N2 doping treatments at Fermilab[C]//The 17th International Conference on RF Superconductivity. 2015: 423-427.
[3] Ge Mingqi, Eichhorn R, Elmore B, et al. Performance of nitrogen-doped 9-cell SRF cavities in vertical tests at Cornell University[C]//The 17th International Conference on RF Superconductivity. 2015: 328-332.
[4] Konomi T, Dohmae T, Hori Y, et al. Trial of nitrogen infusion and nitrogen doping by using J-PARC furnace[C]//The 18th International Conference on RF Superconductivity. 2017: 775-778.
[5] Sha Peng, Liu Baiqi, Zhang Xinying, et al. R&D of CEPC cavity[C]//The 18th International Conference on RF Superconductivity. 2017: 463-465.
[6] Palczewski A D, Marhauser F. Material qualification of LCLS-II production niobium material including RF and flux expulsion measurements on single cell cavities[C]//Proc of The 28th Linear Accelerator Conference. 2016: 199-202.
[7] Melnychuk O S, Grassellino A, Lewis F, et al. Vertical cavity test facility at Fermilab[C]//The 17th International Conference on RF Superconductivity. 2015: 534-538.
[8] Martinello M, Grassellino A, Checchin M, et al. Effect of interstitial impurities on the field dependent microwave surface resistance of niobium[J]. Applied Physics Letters, 2016, 109: 062601. doi: 10.1063/1.4960801
[9] Checchin M, Martinello M, Melnychuk O S, et al. New insight on nitrogen infusion revealed by successive nanometric material removal[C]//The 9th International Particle Accelerator Conference. 2018: 2665-2667.
[10] Martinello M, Aderhold S, Chandrasekaran S K, et al. Anti-Q-slope enhancement in high-frequency niobium cavities[C]//The 9th International Particle Accelerator Conference. 2018: 2707-2709.