Modeling field ionization in an energy conserving form and resulting nonstandard fluid dynamics

A fluid model that takes the field ionization energy correctly into account is presented for the first time by introducing an energy conserving ionization current as a source term in the wave equation. Nonstandard type fluid equations result from the finite ejection energy of the electrons in the field ionization process. The energy and momentum distributions of the ejected electrons are obtained from the time-dependent Schrödinger equation and classical Monte Carlo calculations. Characteristic results of how field ionization influences the pulse propagation, and some extremely nonlinear features caused by the ionization current are given.