Over-barrier side-band electron emission from graphene with a time-oscillating potential

We propose a model which describes side-band electron emission from vertically aligned monolayer graphene with an internal time-oscillating barrier and a static edge barrier. Our results show that electron emission is governed by the over-barrier emission process, which is dominated by the time-oscillating barrier. The emitted current line density J [nA/nm] is only dependent on the amplitude V1 and on the frequency ω of the time-oscillating barrier, and is characterized by 0<γ=V1/ℏω<1. From the model, it is found that J is maximized at about ω=1014 rad/s to 1015 rad/s, and that J increases with γ.