|TUYD4||Towards High Brightness from Plasmon-Enhanced Photoemitters||285|
Funding: This work is supported by DOE BES Contract No. DE-AC02-05CH11231. C.P. acknowledges NSF Award PHY-1549132 (CBB) and the US DOE SCGSR program. DD was supported by NSF Grant No. DMR-1548924 (STROBE).
Plasmonic cathodes, whose nanoscale features may locally enhance optical energy from the driving laser trapped at the vacuum interface, have emerged as a promising technology for improving the brightness of metal cathodes. A six orders of magnitude improvement  in the non-linear yield of metals has been experimentally demonstrated through this type of nanopatterning. Further, nanoscale lens structures may focus light below its free-space wavelength offering multiphoton photoemission from a region near 10 times smaller  than that achievable in typical photoinjectors. In this proceeding, we report on our efforts to characterize the brightness of two plasmonic cathode concepts: a spiral lens and a nanogroove array. We demonstrate an ability to engineer and fabricate nanoscale patterned cathodes by comparing their optical properties with those computed with a finite difference time domain (FDTD) code. The emittance and nonlinear yield of the cathodes are measured under ultrafast laser irradiation. Finally, prospects of this technology for the control and acceleration of charged particle beams are discussed.
 Polyakov, A., et al. (2013). Physical Review Letters, 110(7), 076802.
 Durham, D. B., et al. (2019). Physical Review Applied, 12(5), 054057.
|Slides TUYD4 [7.160 MB]|
|DOI •||reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUYD4|
|About •||Received ※ 05 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 13 September 2022|
|Cite •||reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)|