Vibrational strong coupling of organogel membrane in optical microcavity

Vibrational polaritons arise from the strong coupling between cavity photons and molecular vibrational transitions. In this work, an organogel membrane is used to spatially define the number and position of molecules within an optical microcavity, laying the foundation for studying polariton behavior in multiphase-filled systems. By adjusting the cavity length and organogel membrane thickness (including the air gap), precise control of the coupling strength is achieved. Experimental results show that the Rabi splitting energy is linearly proportional to the square root of the organogel membrane thickness, and the findings are reproduced through classical cavity transmission simulations and the theoretical two-oscillator model. These findings provide a new method for spatially controlling strongly coupled systems and help deepen our understanding of polaritons in complex molecular systems.