Enhanced ionization of the molecular ion H₂⁺ in intense laser and static magnetic fields

The three-dimensional time-dependent Schrödinger equation is solved exactly for the H₂⁺ molecular ion as a function of internuclear distance R in a short intense laser field pulse and a static magnetic field, parallel to the internuclear axis, using a numerical integration method. Previous calculations of laser-induced ionization in this ion for zero magnetic field [Phys. Rev. A 48, 3837 (1993); 52, 2511 (1995)] demonstrated the phenomenon of charge-resonance-enhanced ionization (CREI) at critical distances R_c, due to Stark displacements of the lowest unoccupied molecular orbital (LUMO) above internal proton Coulomb and static laser field barriers. The presence of the magnetic field allows for controlling the energy displacements of the LUMO and consequently control of CREI, thus confirming CREI as a quasistatic electron tunneling process in the nonsymmetric double-well potential created by protons and a laser field.