Highly Sensitive Photonic Sensor Based on V-Shaped Channel Mediated Gold Nanowire

This paper presents a highly sensitive Surface Plasmon Resonance (SPR) biosensor using gold (Au) nanowires mediated single and double V-Shaped Channels (VSC). The proposed sensor consists of an Au nanowire placed under the VSC region, which is coupled to the light source. The sensing process is performed through the mediation of the SPR between the surface plasmon polaritons and the core guided modes of the VSC, which is later filled with analytes to be measured. The sharp edge of the VSC enhances the concentration of the magnetic fields allowing the detection of small changes in the refractive index of the analytes (biomolecules). Due to the important optical properties of the nanowire in nanoscale confinement, the inner and outer radii are optimized to obtain high sensitivity. The sensitivity is calculated to be 9230 nm/Refractive Index Unit (RIU) for a single VSC, while it is greatly enhanced reaching 15384 nm/RIU for double VSC system. The double V channels have distinctive responses to different analytes, which enables simultaneous sensing of various biomolecules. These excellent properties of the proposed Proof of Concept (PoC) photonic sensor pave the way to design multichannel compact sensors for a wide range of applications varying from chemical to biological sensing and detecting the cellular origin of infectious disease.