Publications

2025

• Electric fields, forces, and modification of the tunnel barrier during field electron emission and field evaporation from single-wall carbon nanotubes
  
  • Pimonov Vladimir
  • Panciera Federico
  • Rouille Goulven
  • Weng Catherine
  • Perisanu Sorin
  • Cojocaru Costel Sorin
  • Taoum Haifa
  • Wei Chen
  • Barranco Carceles Salvador
  • Verdugo-Gutiérrez Victor
  • Aguili Ilias
  • Sivignon Jean Francois
  • Blanchard Nicholas
  • Legagneux Pierre
  • Purcell Stephen Thomas
  • Ayari Anthony
  • Vincent Pascal
  Journal of Vacuum Science & Technology B, Nanotechnology and Microelectronics, AVS through the American Institute of Physics, 2025, 43 (4), pp.043202. In this paper, we theoretically and experimentally investigate the specificities of single-walled carbon nanotubes (SWNTs) for field electron emission (FE) and field ion evaporation (FI). For FE, the small radii of curvature of these nanotubes lead to a significant widening of the tunnel barrier, and thus, for a given emission current, the fields at the surface of the SWNTs are significantly higher than commonly observed in standard large radius FE. For currents in the μA range, for example, fields ranging from 7–8 V/nm for large nanotubes to 17–18 V/nm for the thinnest are required. These strong fields, in turn, have repercussions on FI and electrostatic forces. The electric fields and longitudinal electrostatic forces during FE and FI as a function of nanotube radius are presented. The evolution of the nanotube during field evaporation was also studied in an environmental transmission electron microscope as a function of field strength and polarity. A strong dissymmetry between positive and negative polarity is observed. For negative polarity, the nanotubes can gradually shorten as the voltage is increased, whereas in positive polarity, they are almost systematically torn off before apex evaporation occurs. A model to explain this dissymmetry for our samples is presented. These results can be used to optimize nanotube cathode geometries. (10.1116/6.0004707)
  DOI : 10.1116/6.0004707