High-sensitivity label-free optical fiber optrodes based on the excitation of Bloch surface waves

摘要: In this study, the possibility to excite Bloch surface waves (BSWs) on tip of a single-mode optical fiber is explored for first time. particular, we show achieve an on-tip excitation BSWs, with optimized characteristic arising resonances, via “all-fiber” grating-coupled configuration. Furthermore, envisioning novel high-performance nanoprobes for label-free biosensing, introduce ad hoc design aimed at maximizing the refractive-index sensitivity. Numerical results indicate that estimated sensitivities are comparable those exhibited by current plasmonic lab-on-tip bio-probes, but accompanied higher spectral selectivity. Therefore, this preliminary work paves way development new classes miniaturized surface-wave fiber devices low-detection-limit chemical and biological sensing.