Influence of magnetic field on I-V relations of spherical cathode diode

Magnetic field affects strongly characteristics of spherical cathode diode. The numerical research shows that the effect of magnetic field (include self-magnetic field and external magnetic field) on diode takes place via varying the tracks of electron beam. The space charge limited current decreases as external applied magnetic field increases. With intense enough external applied magnetic field, the space charge limited current of diode is about half of the current without external applied magnetic field. In conditions without external applied magnetic field, radius of beam at anode surface and enhancement factor of space charge limited current both tend to decrease with increasing diode current.