Optical Fiber Tip Functionalized by Colloidal Photonic Crystal and Gold Nano-Particles for SERS Sensing

This work explores metal-dielectric colloidal crystal (MDCC) structures as SERS sensing layer. The MDCCs are fabricated directly onto optical fiber tip surface by successive depositions of PS Colloidal Crystal (CC) and Au NanoParticles. The fiber device is explored as remote SERS probe in optrode configuration. The MDCC permits to combine localized surface plasmon resonance (LSPR) of noble metallic nanoparticles and photonic bandgap (PBG) of colloidal type photonic crystals (PhCs). For the sensing test, the fiber probes were immersed in a 100μM aqueous solution of Rhodamine (R6G). Then, preliminary SERS results were retrieved by a Labspec Aramis confocal Raman spectrometer.