Your Search Results

Use this resource - and many more! - in your textbook!

AcademicPub holds over eight million pieces of educational content for you to mix-and-match your way.

Experience the freedom of customizing your course pack with AcademicPub!
Not an educator but still interested in using this content? No problem! Visit our provider's page to contact the publisher and get permission directly.

On the screening of the electric field at the cathode surface by an electron space charge at intense field emission

By: Batrakov, A.V.; Proskurovsky, D.I.; Pegel, I.V.;

1998 / IEEE / 0-7803-3953-3

Description

This item was taken from the IEEE Conference ' On the screening of the electric field at the cathode surface by an electron space charge at intense field emission ' The paper considers the effect of the space charge of emitted electrons on the electric field at the tip of a field emitter. To analyze this phenomenon, the Poisson equation was solved numerically for a spherical vacuum diode with a field emission cathode. The dependence of the actual electric field on the geometric electric field has been compared with the known approximate dependencies. Strong screening of the electric field at the cathode by the space charge of emitted electrons at fields over 5/spl times/10/sup 7/ V/cm is noted. Based on the obtained dependencies of the actual field on the geometric one and using the SuperSAM code, the field emission occurring in a Muller projector has been simulated. It has been shown that the ""ring effect"" appearing in field emission patterns can well be explained by the field emission from the peripheral regions of the field emitter. The current density distributions over the surface and in the bulk of the emitter have been analyzed.