A Study of Macroscopic Emission Non-Uniformity in Thermionic Cathodes Due to Profilimetry Variation

Abstract

We develop a model to show that the micron-scale ridges due to surface machining of thermionic dispenser cathodes may cause significant angular variations in the macroscopic current density on ring-shaped cathodes as are commonly used in gyrotrons. The local field enhancement caused by the ridges resulting from machining gives an angular variation in current that may be pronounced. An explanation in terms of wobble of the cathode during machining and the eccentricity of the cathode cross-section can explain much of the observed variation.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 2006
Accession Number
ADP022465

Entities

People

  • Kevin L. Jensen
  • Nicholas Jordan
  • Yueying Lau

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Advanced Electronics
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Amplifiers
  • Current Density
  • Dispensers
  • Electronics
  • Electrons
  • Emission
  • Free Electron Lasers
  • Free Electrons
  • Gyrotrons
  • Machining
  • Military Research
  • Power Amplifiers
  • Technical Information Centers
  • Thermionic Emission
  • Vacuum Electronics
  • Work Functions

Fields of Study

  • Physics

Readers

  • Electronics Engineering
  • Manufacturing Engineering.
  • Materials Science and Engineering.