Planar ultrananocrystalline diamond field emitter in accelerator radio frequency electron injector: Performance metrics

• Published in: Applied physics letters 2014-11, Vol.105 (20)
• Main Authors: Baryshev, Sergey V., Antipov, Sergey, Jing, Chunguang, Qiu, Jiaqi, High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, Shao, Jiahang, Liu, Wanming, Gai, Wei, Pérez Quintero, Kenneth J., Sumant, Anirudha V., Kanareykin, Alexei D.
• Format: Article
• Language: English
• Subjects: CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DIAMONDS; ELECTRON GUNS; FIELD EMISSION; GHZ RANGE 01-100; LAYERS; MEV RANGE 01-10; NANOSTRUCTURES; NEODYMIUM LASERS; NITROGEN; STAINLESS STEELS
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4901723

A case performance study of a planar field emission cathode (FEC) based on nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, was carried out in an RF 1.3 GHz electron gun. The FEC was a 100 nm (N)UNCD film grown on a 20 mm diameter stainless steel disk with a Mo buffer layer. At surface gradients 45–65 MV/m, peak currents of 1–80 mA (equivalent to 0.3–25 mA/cm{sup 2}) were achieved. Imaging with two YAG screens confirmed emission from the (N)UNCD surface with (1) the beam emittance of 1.5 mm × mrad/mm-rms and (2) longitudinal FWHM and rms widths of non-Gaussian energy spread of 0.7% and 11% at an electron energy of 2 MeV. Current stability was tested over the course of 36 × 10{sup 3} RF pulses (equivalent to 288 × 10{sup 6 }GHz oscillations)