The field emission characteristics under transient electric field

This article concentrates on the field emission (FE) characteristics under the pulsed transient electric field. Experimental measurements are carried out by applying direct current (DC) voltage, millisecond pulse voltage, and microsecond pulse voltage. Additionally, 304 stainless steel, oxygen-free copper and titanium electrodes are utilized to verify the consistency. Compared with the case under DC electric field, three distinctive FE characteristics are observed under pulsed transient electric field: the regular emission, the intense emission, and the annihilation phenomenon. First, the emission starting point implies one strong correlation with the second partial derivative of transient electric field strength with respect to time. Second, the emission current under pulsed electric field is much higher than that under the DC electric field. Moreover, the FE current is deeply associated with the gradient of the electric field during the rising front. Third, the FE current is extinguished though there is still high transient electric field. The mechanism of the three characteristics is still unclear and should be the subject of further investigation.