Simulation of Sub-Femtosecond Response in Laser-Assisted Field Emission

A new type of ultrafast optoelectronic device is described that shows promise for producing sub-femtosecond pulses of current. In this device a pulsed laser is focused on a nanoscale tip so that the time-dependent electric field of the radiation is superimposed on the applied static field to cause a sudden increase in the current of the emitted electrons. Simulations have been used to optimize the parameters of this, device in order to reduce the time that it takes for the current to respond to the incident radiation to less than one femtosecond