Characteristics of the Trochoidal Electron Monochromator

Abstract

An electron monochromator for use in an axial magnetic field is described. Electrons are injected parallel to the magnetic field and an electric field is applied in a perpendicular direction. The electrons thus describe trochoids and drift in a direction perpendicular to both the electric and magnetic fields and disperse according to their initial velocities. An electron energy width at half-maximum of 0.020 eV can be obtained, with a transmitted current of about 10−9 A.