title: Hybrid structured fiber-optic Fabry-Perot interferometer for simultaneous measurement of strain and temperature.
abstract: We fabricate and experimentally demonstrate a hybrid structured Fabry-Perot interferometer (FPI) embedded in the middle of a fiber line for simultaneous measurement of axial strain and temperature. The FPI is composed of a silica-cavity cascaded to a spheroidal air-cavity, both of which are formed in a hollow annular core fiber (HACF). The fabrication process of the FPI includes only a fusion splice between a single-mode fiber and a HACF and several electrical arc discharges at the HACF near the splice point. Experimental results show that the strain and temperature sensitivities of the air-cavity can be 5.2 pm/με and 1.3 pm/C°, respectively, and those of the silica-cavity can be 1.1 pm/με and 13 pm/C°, respectively. The different sensitivities of silica-cavity and air-cavity to strain and temperature enable us to implement simultaneous sensing in strain and temperature.
authors.forename: Ai
authors.initials: A
authors.lastname: Zhou
authors.forename: Boyang
authors.initials: B
authors.lastname: Qin
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zhu
authors.forename: Yaxun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhihai
authors.initials: Z
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Libo
authors.initials: L
authors.lastname: Yuan