Figure 5
On-the-fly dressed-state model of optical excitations of two classically-colliding cold ground-state \(^{23}\hbox {Na}^{87}\)Rb molecules in the presence of an infra-red trapping laser with a wavelength of 1064 nm. Panels (a)-(d) show singlet ground- (solid black curve) and excited-states (solid red, blue, and grey curves) potential energies as functions of time during the first few ps of trajectories with zero impact parameter, but different initial relative orientations and velocities of the cold molecules. These initial orientations and velocities are shown in the four small panels on the right with corresponding panel labels. Large magenta and smaller green filled circles give the positions of Rb and Na atoms, respectively, while arrows of different lengths specify their velocities. The second higher-in-energy black curves in the panels on the left correspond to the ground-state potential plus the energy of a photon from the 1064 nm laser. Excitations occur when this dressed ground-state potential crosses that of excited states. The error bands on the potentials of the first (orange curve) and second (blue curve) excited states indicate the difference in energy splittings between excited states and the ground state as found by TD-DFT and EOM-CCSD calculations. Figures were prepared using Grace-5.1.22 software.
