Fig. 1: Diabatic single- and multiphoton light-induced molecular potentials.

a Angle-dependent potential energy surfaces of H₂⁺ dressed by a linearly polarized, moderately intense, visible (685 nm, 3 × 10¹³ W/cm²) laser field. The nuclear potential energy E is plotted as a function of the internuclear distance R, and the angle θ between the molecular axis and the laser polarization. The LICI at the one-photon crossing is marked by a 1. The potential energy curve shown in b corresponds to a lineout along the internuclear distance R through the LICI. The dotted line marks the position of the one-photon resonance between the σ_g and σ_u states. The potential energy diagram in c, shows several multiphoton crossings between the σ_g (dissociation limits of (…, 0, −2, −4,…) ω_IR) and σ_u (dissociation limits of (…, 1, −1, −3, …) ω_IR) states in a 2300 nm dressing field. Two of these states are labeled, and the location of multiphoton transitions of order 7, 5, 3, and 1 (from left to right) are indicated by dashed lines. d Same as a for a mid-IR dressing field (2300 nm, 3 × 10¹³ W/cm²). Structures attributed to 1, 3, and 5 photon couplings are marked. e Calculated proton momentum distributions produced by a 2300 nm, 3 × 10¹³ W/cm² laser field polarized along the z-axis. The color scale indicates the proton yield. Contributions from dissociation on the σ_g and σ_u surfaces are shown separately, and structures attributed to the 1, 3, and 5 photon couplings are indicated.