High intensity, plasma-induced electron emission from large area carbon nanotube array cathodes

Abstract

The plasma-induced electron emission properties of large area carbon nanotube (CNT) array cathodes under different pulse electric fields were investigated. The formation and expansion of cathode plasmas were proved; in addition, the cathodes have higher emission current in the double-pulse mode than that in the single-pulse mode due to the expansion of plasma. Under the double-pulse electric field of 8.16 V/μm, the plasma’s expansion velocity is about 12.33 cm/μs and the highest emission current density reached 107.72 A/cm2. The Cerenkov radiation was used to diagnose the distribution of electron beams, and the electron beams’ generating process was plasma-induced emission.