Anisotropy of thermionic electron emission values for LaB6 single-crystal emitter cathodes

Abstract

Measurement of thermionic electron emission values for pointed LaB6 single-crystal emitter cathodes has shown that 〈110〉 axial orientations yield emission values ten times higher than 〈100〉 orientations at 1545 °K. Minimum values were obtained for the 〈510〉 directions. These findings seem encouraging in achieving perhaps two orders of magnitude higher emission fluxes as compared to tungsten emitters.