  High resolution molecular dynamics simulations with full Coulomb interactions
of electrons are used to investigate field emission in planar nanodiodes. The
effects of space charge and emitter radius are examined and compared to
previous results concerning transition from Fowler-Nordheim to Child-Langmuir
current. The Fowler-Nordheim law is used to determine the current density
injected into the system and the Metropolis-Hastings algorithm to find a
favourable point of emission on the emitter surface. A simple fluid like model
is also developed and its results are in qualitative agreement with the
simulations.
