Ponderomotive tunneling in electron-laser interactions

It is known that the ponderomotive potential from the laser electron interaction behaves like a static potential that scatters off electrons. We have investigated the process of the electron tunneling the ponderomotive potential by using the nonperturbative quantum electrodynamic approach with a modified Gaussian quantized laser field. The results show that the ponderomotive tunneling is significantly larger than the tunneling of a static potential of the same profile. The tunneled electron is discrete in energy spectrum and spatial diffraction as the result of multiphoton processes. A resonant tunneling occurs when the ponderomotive energy equals the multiple integer of the laser photon energy.