Surface plasmon resonance-like integrated sensor at terahertz frequencies for gaseous analytes

Plasmon-like excitation at the interface between fully polymeric fiber sensor and gaseous analyte is demonstrated theoretically in terahertz regime. Such plasmonic excitation occurs on top of a approximately 30 microm ferroelectric PVDF layer wrapped around a subwavelength porous polymer fiber. In a view of designing a fiber-based sensor of analyte refractive index, phase matching of a plasmon-like mode with the fundamental core guided mode of a low loss porous fiber is then demonstrated for the challenging case of a gaseous analyte. We then demonstrate the possibility of designing high sensitivity sensors with amplitude resolution of 3.4 x 10(-4) RIU, and spectral resolution of 1.3 x 10(-4) RIU in THz regime. Finally, novel sensing methodology based on detection of changes in the core mode dispersion is proposed.