Electron emission from metal emitters subject to a high intensity laser in the presence of DC electric fields

Electron emission driven by both a strong DC applied bias and a superimposed laser field is examined through numerical simulations. Heating at the electrode surface that creates a dynamic, nonequilibrium electron distribution is included based on appropriate rate-equation analyses for energy balance. Much higher emission currents are predicted that follow the AC oscillations over the femtosecond range. The hot carrier population are predicted to persist much longer to yield a more gradual decay in the emission current beyond laser termination. The numerical results are also extended to an emitter array, given the interest in such configurations for obtaining high output coherent currents. The capability can subsequently be extended to assess the coherence and emittance of the electron source based on Monte Carlo transport techniques.