Multiple hybridized resonances of IR-806 chromonic molecules strongly coupled to Au nanorods

Abstract

Strong coupling of plasmons and molecules generates intriguingly hybridized resonance. The IR-806 molecule is a near-infrared cyanine liquid crystal dye with multiple molecular bands and its tunable absorption spectrum varies dramatically with concentration. In this article, we investigate multiple hybridized resonances of the Au nanorods (AuNRs) strongly coupled to IR-806 molecules. Five hybridized resonance peaks are observed in the extinction spectra of the AuNR@IR-806 hybrids. Two resonance peaks at approximately 840 and 912 nm in the hybrids are reported for the first time. The dependence of the multiple hybridized peaks on the bare plasmon resonance wavelength of AuNRs and the molecular concentration is also demonstrated. The observations presented herein provide a plasmon–molecule coupling route for tuning optical responses of liquid crystal molecules.