Controlling Autler–Townes Splitting of the K ₂ Molecule with Quantum Light

Autler–Townes splitting (ATS) is a hallmark phenomenon of strong light–matter interaction, in which the resonant photoelectron energy spectrum splits into distinct peaks when driven by a strong electromagnetic field. We investigate the Autler–Townes Splitting (ATS) in K2 molecules with quantum light. The triple splitting structures originating from three-photon ionization are analyzed under different types of driving fields, including bright squeezed vacuum (BSV), phase-squeezed coherent (PSC) light and amplitude-squeezed coherent (ASC) light by numerically solving the time-dependent Schrödinger equation. Compared with the results with the coherent-state (classical) light drive, we show that the ATS dynamics is sensitive with the squeezing parameter of quantum light, leading to modifications of the subband structures and splitting magnitudes. In particular, a BSV pulse exhibits a higher splitting efficiency than a classical pulse of the same mean intensity. This work has implications on ultrafast coherent control of molecular reactions with quantum light.