Crossed-field secondary emission electron source

The authors suggested recently the idea of producing high current, high frequency modulated electron beams based on the amplification of a small (few mA) primary current with the aid of a secondary emission multiplier. The multiplier must be capable of producing an output current of 100 A and, at the same time, must not significantly distort the primary current modulation at GHz frequencies of operation. At low levels of output current, the electron multipliers were shown to operate successfully at frequencies as high as 4 GHz. Because conventional secondary emission amplifiers can operate only at currents below 1 mA, the most important task is to create a multiplier with the ability to produce high output currents. For this purpose, the authors have proposed some modifications to channel electron multipliers and these are currently undergoing experimental evaluation. In this paper, they describe another novel concept for an electron source based on a mechanism of electron multiplication in crossed electric and magnetic fields