Skip to content
6CCVD Research

Effect of material composition of diamond field emission array cathodes on quality of transversely shaped beams

At a Glance

Section titled ā€œAt a Glanceā€
MetadataDetails
Publication Date2023-01-30
JournalApplied Physics Letters
AuthorsMitchell Schneider, Heather Andrews, Sergey V. Baryshev, Emily Jevarjian, D. Kim
InstitutionsMichigan State University, Argonne National Laboratory
Citations3

Abstract

Section titled ā€œAbstractā€

Diamond field emitter array field emission cathodes (DFEA FECs) are attractive for the next generation of injectors due to their ability to produce transversely shaped beams without the need for complex masking or laser schemes. However, reliability of this cathode technology remains a challenging issue as principal mechanisms guiding and allowing for output beam shaping remained poorly understood. This paper reports the results of testing two DFEA FECs with the same pattern and emitter tip geometry. Although both cathodes were able to sustain gradients of 44 MV/m and produce maximum output integral charge of 0.5 nC per radio frequency pulse, their emission patterns were different. One cathode did not produce a shaped beam, while the other one did. This difference was explained by the extent of the local variations of the diamond material across the arrays as discovered by spatially resolved Raman spectroscopy. The main practical takeaways were (i) tip sharpness was not a prerequisite for producing a shaped beam and instead (ii) material characteristics resulting in different cathode ballast resistance affected emission spatial uniformity across the array and hence the beam shaping.

Tech Support

Section titled ā€œTech Supportā€

Original Source

Section titled ā€œOriginal Sourceā€

References

Section titled ā€œReferencesā€
  1. 2009 - New local field quantity describing the high gradient limit of accelerating structures [Crossref]
  2. 2021 - Ampere-class bright field emission cathode operated at 100ā€‰ā€‰MV/m [Crossref]
  3. 2015 - Direct observation of electron emission from grain boundaries in CVD diamond by peakforce-controlled tunnelling atomic force microscopy [Crossref]
  4. 1999 - Mechanisms of electron field emission from diamond, diamond-like carbon, and nanostructured carbon [Crossref]
  5. 2020 - Demonstration of transport of a patterned electron beam produced by diamond pyramid cathode in an rf gun [Crossref]
  6. 2020 - Shaped beams from diamond field-emitter array cathodes [Crossref]
  7. 2018 - Fabrication of micron-scale diamond field emitter arrays for dielectric laser accelerators
  8. 2019 - High power conditioning and benchmarking of planar nitrogen-incorporated ultrananocrystalline diamond field emission electron source [Crossref]
  9. 2021 - Confirmation of transit time-limited field emission in advanced carbon materials with a fast pattern recognition algorithm [Crossref]
  10. 2021 - Cryogenic operation of planar ultrananocrystalline diamond field emission source in SRF injector [Crossref]

Reads Similar to This

Structural Change of DLC Film Heated by Laser Irradiation, Analyzed using Surface Enhanced Raman Spectroscopy Optical localization of a nitrogen-vacancy center in three-dimensional space via probe absorption Universal peroxide formation and Fermi level alignment in semiconductors due to ambient air-induced surface transfer doping