title: Ultraweak intrinsic Fabry-Perot cavity array for distributed sensing.
abstract: This Letter reports on an ultraweak intrinsic Fabry-Perot interferometer (IFPI) array fabricated by a femtosecond (fs) laser for distributed sensing applications. Ultralow reflectors (<-60  dB) were obtained. IFPIs with different physical lengths showed identical temperature sensitivity (-1.5  GHz/°C). A distributed temperature sensing test was conducted. No crosstalk between IFPI elements in the array was observed, implying the device's utility as a distributed sensing system. The possibility of using smaller bandwidths for sensor interrogation was experimentally proven. A small-scale temperature distribution test was conducted on a continuously cascaded ultraweak IFPI array, demonstrating its high spatial resolution. The temperature detection limit of this system was measured to be less than 0.0667°C.
authors: Zhen
authors: Z
authors: Chen
authors: Lei
authors: L
authors: Yuan
authors: Gerald
authors: G
authors: Hefferman
authors: Tao
authors: T
authors: Wei
mesh_terms: D007368:Interferometry / Q000295:instrumentation*; D007834:Lasers; D055100:Optical Fibers; D013696:Temperature