Remote Non-Invasive Fabry-Pérot Cavity Spectroscopy for Label-Free Sensing

Journal Article

Fabry–Pérot cavities provide a highly sensitive platform for optical sensing through the dependence of their transmission and reflection spectra on the optical properties of the cavity environment. In this work, we investigate and demonstrate a non-invasive and remote approach to label-free molecular sensing based on the interaction between target molecules and the electromagnetic field reflected from a Fabry–Pérot cavity. Molecular scattering introduces additional spectral features into the cavity reflection spectrum, whose amplitudes provide a measurable signature of the molecular concentration. We further demonstrate that employing an array of Fabry–Pérot cavities enables simultaneous interrogation over a broad spectral range, thereby facilitating the acquisition of characteristic optical fingerprints of target molecular species. The proposed approach establishes a remote, non-invasive spectroscopic framework for label-free molecular detection and provides a basis for developing scalable cavity-based sensing architectures.