By Topic

Light Emission From CsI-Coated Carbon Velvet Cathodes Under Varied Conditions

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

5 Author(s)
Lynn, C.F. ; Center for Pulsed Power & Power Electron., Texas Tech Univ., Lubbock, TX, USA ; Neuber, A.A. ; Walter, J.W. ; Dickens, J.C.
more authors

Many high-power electron devices utilize cold-cathode diodes to generate intense electron beams. These cold cathodes have the advantage of being capable of supplying several kiloamperes of current spread over a large cross section without the need for auxiliary components such as a heater supply. However, they suffer from many known problems such as nonuniform emission that can result in small areas of high current density on the anode and, thus, excessive anode heating. As a consequence, outgassing and vaporization of bulk material frequently leads to premature impedance collapse. Hence, minimizing nonuniform anode heating due to beam nonuniformity is paramount. As previously demonstrated, the use of a CsI-coated carbon velvet cathode improved beam uniformity, reduced outgassing, and mitigated early impedance collapse. To quantify the uniformity, temporal and spatially resolved images of the cathode plasma were taken for a CsI-coated carbon fiber cathode, operated at an average current density of ~150 A/cm2 under various conditions, i.e., without a field shaping ring, before and after discharge cleaning, and with a field shaping ring. All cathodes were operated in a sealed tube with a small integrated sputter ion pump to restore vacuum levels to 10-9 torr levels between subsequent shots.

Published in:

Plasma Science, IEEE Transactions on  (Volume:40 ,  Issue: 12 )