Plasmonic Photonic-Crystal Slabs: Visualization of the Bloch Surface Wave Resonance for an Ultrasensitive, Robust and Reusable Optical Biosensor

Crystals

Alexander V. Baryshev¹  Alexander M. Merzlikin² 

[1] Ioffe Physical-Technical Institute, Politekhnicheskaya 26, St. Petersburg 194021, Russia;Institute for Theoretical and Applied Electromagnetics, Izhorskaya 13, Moscow 125412, Russia; E-Mail:

关键词: plasmonic photonic crystal;    surface Bloch wave;    surface plasmon;    biosensor;   

DOI  :  10.3390/cryst4040498

来源: mdpi

【 摘 要 】

A one-dimensional photonic crystal (PhC) with termination by a metal film—a plasmonic photonic-crystal slab—has been theoretically analyzed for its optical response at a variation of the dielectric permittivity of an analyte and at a condition simulating the molecular binding event. Visualization of the Bloch surface wave resonance (SWR) was done with the aid of plasmon absorption in a dielectric/metal/dielectric sandwich terminating a PhC. An SWR peak in spectra of such a plasmonic photonic crystal (PPhC) slab comprising a noble or base metal layer was shown to be sensitive to a negligible variation of refractive index of a medium adjoining to the slab. As a consequence, the considered PPhC-based optical sensors exhibited an enhanced sensitivity and a good robustness in comparison with the conventional surface-plasmon and Bloch surface wave sensors. The PPhC biosensors can be of practical importance because the metal layer is protected by a capping dielectric layer from contact with analytes and, consequently, from deterioration.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.