Static-field-induced states and their manifestation in tunneling ionization dynamics of molecules

The physical origin and properties of quasistationary static-field-induced states (SFISs) are discussed. SFISs can be supported by a combination of any atomic or molecular potential and an external static electric field and do not have counterparts in the absence of the field. A resonant tunneling ionization (RTI) mechanism of molecules proceeding via SFISs is analyzed for a one-dimensional model. It is shown that SFISs manifest themselves as peaks of the tunneling ionization rate both in static and time-dependent fields in the adiabatic regime. The peaks are located along the RTI ridges in the plane of internuclear distance R and the momentary value of electric field F. The RTI via SFISs appears to be one of the general ionization mechanisms of molecules.