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Article: Electron sources for microwave amplifiers.(NANOTECHNOLOGY)
- Article from:
- Advanced Ceramics Report
- Article date:
- December 1, 2005
CopyrightCOPYRIGHT 2005 International Newsletters. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Researchers at the University of Cambridge, UK, and Thales Research and Technology, France, have developed carbon nanotubes for use as cold cathodes in high power microwave amplifiers.
The carbon nanotube arrays developed by the researchers emit electrons directly by turning on and off in response to a radio frequency (RF) input signal, in a process known as temporal modulation, producing electrons with a peak current of 12 A.[cm.sup.-2] at a pulse frequency of 1.5 GHz.
Each cold cathode contains 2500 carbon nanotubes, with each nanotube spaced at twice its height apart from the next one to give maximum electrostatic efficiency.
Moreover, to ...