Fluorimetry in the Strong-Coupling Regime: From a Fundamental Perspective to Engineering New Tools for Tracing and Marking Materials and Objects

Under exceptional circumstances, light and molecules bond together, creating new hybrid light–matter states with far-reaching consequences for these strongly coupled entities. The present article describes the quantum-mechanical foundation of strong-coupling and experimental evidence for molding the radiation properties of nanoprobes by strong-coupling. When applied to tracing and marking, the new fluorometry technique proposed here, which harnesses strong-coupling, has a triple advantage compared to its classical counterparts such as DNA tracing. It is fast, and its signal-to-noise ratio can be improved by spectral filtering; moreover, it reveals a specific quantum signature of the strong-coupling, which is extremely difficult to reproduce classically, thereby opening the door to new anti-counterfeiting strategies.