Reduction of secondary electron yield for E-cloud mitigation laser ablation surface engineering
journal contributionposted on 2017-02-28, 16:45 authored by Reza Valizadeh, O.B. Malyshev, S. Wang, T. Sian, Michael Cropper, N. Sykes
Developing a surface with low Secondary Electron Yield (SEY) is one of the main ways of mitigating electron cloud and beam-induced electron multipacting in high-energy charged particle accelerators. In our previous publications, a low SEY < 0.9 for as-received metal surfaces modified by a nanosecond pulsed laser was reported. In this paper, the SEY of laser-treated blackened copper has been investigated as a function of different laser irradiation parameters. We explore and study the influence of micro- and nano-structures induced by laser surface treatment in air of copper samples as a function of various laser irradiation parameters such as peak power, laser wavelength (λ = 355 nm and 1064 nm), number of pulses per point (scan speed and repetition rate) and fluence, on the SEY. The surface chemical composition was determined by x-ray photoelectron spectroscopy (XPS) which revealed that heating resulted in diffusion of oxygen into the bulk and induced the transformation of CuO to sub-stoichiometric oxide. The surface topography was examined with high resolution scanning electron microscopy (HRSEM) which showed that the laser-treated surfaces are dominated by microstructure grooves and nanostructure features.
European Union’s EuroCirCol collaboration H2020 Framework Programme [grant no. 654305].
Published inApplied Surface Science
CitationVALIZADEH, R. ... et al, 2017. Reduction of secondary electron yield for E-cloud mitigation laser ablation surface engineering. Applied Surface Science, 404, pp.370–379
Publisher© Elsevier B.V.
- AM (Accepted Manuscript)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesThis paper was accepted for publication in the journal Applied Surface Science and the definitive published version is available at https://doi.org/10.1016/j.apsusc.2017.02.013