Interaction between Surface Plasmons and Chiral Molecules Excited by Vortex Light

This paper systematically investigates, via numerical simulations, the plasmon-enhanced chiroptical response and strong interaction between surface plasmons (SP) and chiral molecules in a silver core–chiral molecular shell structure under the excitation of vortex light, focusing on the independent and synergistic effects of spin angular momentum (SAM) and orbital angular momentum (OAM). The results indicate that the addition of an OAM significantly alters the system’s behavior. By tuning the resonance wavelength of the chiral molecules, distinct signatures of Rabi splitting are observed across all of the pairs of the OAM and SAM. Energy level splitting diagrams are summarized to schematically show the distinctions and correlations among these Rabi splittings under different resonance conditions, revealing the physical mechanisms of SAM–OAM cooperative control over chiral plasmon–molecule strong interaction.