Temperature characteristics of microfiber long-period-gratings fabricated by a femtosecond infrared laser

Temperature characteristics of long period gratings (LPGs) in microfibers are investigated. The LPGs are formed by periodic structural perturbation by use of a femtosecond infrared laser. The sensitivity of resonant wavelength to temperature was measured to be around 10 pm/oC, an order of magnitude lower than a typical LPG in conventional single mode fiber.