Zobrazeno 1 - 10
of 193
pro vyhledávání: '"McFadden, Ryan"'
Publikováno v:
AIP Adv. 14, 095320 (2024)
Empirical surface treatments, such as low-temperature baking (LTB) in a gaseous atmosphere or in vacuum, are important for the surface preparation of Nb superconducting radio frequency (SRF) cavities. These treatments inhomogeneously dope the first $
Externí odkaz:
http://arxiv.org/abs/2405.14615
Autor:
Thoeng, Edward, Asaduzzaman, Md., Kolb, Philipp, McFadden, Ryan M. L., Morris, Gerald D., Ticknor, John O., Dunsiger, Sarah R., Karner, Victoria L., Fujimoto, Derek, Junginger, Tobias, Kiefl, Robert F., MacFarlane, W. Andrew, Li, Ruohong, Saminathan, Suresh, Laxdal, Robert E.
Publikováno v:
Sci. Rep. 14, 21487 (2024)
We report direct measurements of the magnetic field screening at the limits of the Meissner phase for two superconducting Nb samples. The samples are processed with two different surface treatments that have been developed for superconducting radio-f
Externí odkaz:
http://arxiv.org/abs/2405.05451
Publikováno v:
Supercond. Sci. Technol. 37, 085006 (2024)
We report measurements of the first-flux-penetration field in surface-treated and coated Nb samples using muon spin rotation ($\mu$SR). Using thin Ag foils as energy moderators for the implanted muon spin-probes, we "profile" the vortex penetration f
Externí odkaz:
http://arxiv.org/abs/2402.15500
Publikováno v:
Appl. Phys. Lett. 124, 086101 (2024)
In a recent Letter by Romanenko et al., the authors used low-energy muon spin rotation (LE-$\mu$SR) to measure the Meissner screening profile in cutouts from Nb superconducting radio frequency (SRF) cavities, systematically comparing how different su
Externí odkaz:
http://arxiv.org/abs/2305.02129
Autor:
Asaduzzaman, Md, McFadden, Ryan M. L., Valente-Feliciano, Anne-Marie, Beverstock, David R., Suter, Andreas, Salman, Zaher, Prokscha, Thomas, Junginger, Tobias
Publikováno v:
Supercond. Sci. Technol. 37 (2024) 025002
Superconducting radio frequency (SRF) cavities, which are critical components in many particle accelerators, need to be operated in the Meissner state to avoid strong dissipation from magnetic vortices. For a defect-free superconductor, the maximum a
Externí odkaz:
http://arxiv.org/abs/2304.09360
Autor:
Ticknor, John O., Adelman, Jonah R., Chatzichristos, Aris, Dehn, Martin H., Egoriti, Luca, Fujimoto, Derek, Karner, Victoria L., Kiefl, Robert F., Levy, C. D. Philip, Li, Ruohong, McFadden, Ryan M. L., Morris, Gerald D., Oudah, Mohamed, Stachura, Monika, Thoeng, Edward, MacFarlane, W. Andrew
Publikováno v:
Phys. Rev. B 108, 195437 (2023)
We report $\beta$-detected nuclear magnetic resonance of ultra-dilute $^{8}$Li$^{+}$ implanted in highly oriented pyrolytic graphite (HOPG). The absence of motional narrowing and diffusional spin-lattice relaxation implies Li$^+$ is not appreciably m
Externí odkaz:
http://arxiv.org/abs/2301.07821
Autor:
McFadden, Ryan M. L., Asaduzzaman, Md, Prokscha, Thomas, Salman, Zaher, Suter, Andreas, Junginger, Tobias
Publikováno v:
Phys. Rev. Appl. 19, 044018 (2023)
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 w
Externí odkaz:
http://arxiv.org/abs/2212.11081
Autor:
McFadden, Ryan M. L., Asaduzzaman, Md, Buck, Terry J., Cortie, David L., Dehn, Martin H., Dunsiger, Sarah R., Kiefl, Robert F., Laxdal, Robert E., Levy, C. D. Philip, MacFarlane, W. Andrew, Morris, Gerald D., Pearson, Matthew R., Thoeng, Edward, Junginger, Tobias
Publikováno v:
J. Appl. Phys. 134, 163902 (2023)
We report measurements of the Meissner screening profile in a Nb(300 nm)/Al$_{2}$O$_{3}$ thin film using $^{8}$Li $\beta$-detected nuclear magnetic resonance ($\beta$-NMR). The NMR probe $^{8}$Li was ion-implanted into the Nb film at energies $\leq$
Externí odkaz:
http://arxiv.org/abs/2212.01137
Autor:
Thoeng, Edward, McFadden, Ryan M. L., Saminathan, Suresh, Morris, Gerald D., Kolb, Philipp, Matheson, Ben, Asaduzzaman, Md, Baartman, Richard, Dunsiger, Sarah R., Fujimoto, Derek, Junginger, Tobias, Karner, Victoria L., Kiy, Spencer, Li, Ruohong, Stachura, Monika, Ticknor, John O., Kiefl, Robert F., MacFarlane, W. Andrew, Laxdal, Robert E.
Publikováno v:
Rev. Sci. Instrum. 94, 023305 (2023)
A new high field spectrometer has been built to extend the capabilities of the $\beta$-detected nuclear magnetic resonance ($\beta$-NMR) facility at TRIUMF. This new beamline extension allows $\beta$-NMR spectroscopy to be performed with fields up to
Externí odkaz:
http://arxiv.org/abs/2211.15619
Autor:
Adelman, Jonah R., Fujimoto, Derek, Dehn, Martin H., Dunsiger, Sarah R., Karner, Victoria L., Levy, C. D. Philip, Li, Ruohong, McKenzie, Iain, McFadden, Ryan M. L., Morris, Gerald D., Pearson, Matthew R., Stachura, Monika, Thoeng, Edward, Ticknor, John O., Ohashi, Naoki, Kojima, Kenji M., MacFarlane, W. Andrew
Publikováno v:
Phys Rev. B 106, 035205 (2022)
We report on the stability and magnetic state of ion implanted $^8$Li in single crystals of the semiconductor ZnO using $\beta$-detected nuclear magnetic resonance. At ultradilute concentrations, the spectra reveal distinct Li sites from 7.6 to 400 K
Externí odkaz:
http://arxiv.org/abs/2109.08637