Discrimination of chemical vapor and temperature effects by using a polarization-maintaining photonic crystal fiber interferometer

Abstract

A reflection-type interferometer based on a polarization-maintaining photonic crystal fiber (PM-PCF) is investigated for simultaneous measurement of chemical vapor and temperature. The PM-PCF with a length of 2.6 cm is fusion-spliced to standard single-mode fiber and airholes of the PM-PCF are fully collapsed allowing the excitation of different core and cladding modes in the PM-PCF corresponding to two orthogonal polarization modes. Since airholes at the end of the PM-PCF interferometer are left open, a chemical vapor can be infiltrated into the voids. Different sensitivities corresponding to input polarization states are utilized for discrimination between chemical vapor and temperature effects.