Laser-Enabled Interatomic Coulomb Decay (ICD) Dynamics in Ar Dimer

We used XUV radiation in combination with an IR laser field to enable \textit{and }control Interatomic Coulomb Decay processes in Ar dimer. A hollow Ar dimer, with a 3s electron kicked-out by a 36 eV XUV pulse, is a weakly bound molecular assembly, vibrating with a period of 300 fs. This 3s hole state decays radiatively since the ICD process is energetically forbidden. By adding the IR laser pulses, we can enable \textit{and/or} control the ICD process as we delay the probe IR pulses relative to the XUV pump pulse. We have studied these processes by utilizing Coulomb-Explosion imaging in a COLTRIMS geometry where we measured full 3D momenta of the coincident Ar$^{+}$ monomers coming from the same Ar dimer. By enabling the ICD process at different internuclear distances of the vibrating hollow Ar dimer, we open different CE channels with a distinctive signature in the measured kinetic energy releases. To the best of our knowledge this is the first work that demonstrates a time-resolved control over an ICD processes.