Strong light-matter coupling for optical switching through the fluorescence and FRET control

Abstract Resonant interaction between excitonic transitions of molecules and localized electromagnetic field forms the hybrid polaritonic states. Tuneable microresonators may change light-matter coupling strength modulate them from weak to strong ultra-strong regimes. In this work we have realised tuneable open-access cavity mode in oligonucleotide-based molecular beacons with their terminus labelled a pair organic dye demonstrating an efficient donor-to-acceptor Förster resonance energy transfer (FRET). We show that predominant photon exciton transition donor molecule can lead such large shift acceptor reservoir mainly lower state be achieved, thus yielding chromophores’ donor–acceptor role reversal or “carnival effect”. The data possibility for confined fields control mediate polariton-assisted remote transfer. Obtained results open avenues quantum optical switching other applications.