A large-scale lithography-free plasmonic color filter for effectively glucose sensing

A large-scale lithography-free plasmonic color filter (PCF) is presented, which is integrated with a microfluidic chip for effective glucose sensing. PCF is composed of hybrid nanopillars fabricated with SiO
₂
and Au thin-films on Si substrate. It exhibits angle-independence, and polarization-independence, which are the most important factors for color filters for industrial applications. The resonance shift is 56 nm with a stable bandwidth (~30nm) by varying concentration of glucose solution. The sensitivity is 157.61 nm/RIU and the corresponding figure-of-merit is 5.25. Such strategy can be exploited to further potentially enter the ultra-strong coupling regime in chemical solution sensors.