Laser induced field emission from metallic field emitters: Near field enhancement of optical electric field at metallic nano-surfaces

Efficient laser-induced field emission excited by femtosecond near infrared laser pulses from metallic field emitter array cathodes has been reported recently. To elucidate the physical processes, we studied the electromagnetic field distribution at the nanometer-scale metallic field emitter apexes numerically and compared with experimental laser-polarization dependence. Good agreement between theory and experiment indicates the essential role of the nano-optical field enhancement at the metallic nano-tips.