Fabrication of a temperature-insensitive transverse mechanical load sensor by using a photonic crystal fiber-based Sagnac loop

An optical fiber transverse mechanical load sensor is fabricated by using a short section of a solid core photonic crystal fiber (PCF) which is inserted inside a Sagnac fiber loop. An initial transverse force is applied on the PCF to introduce necessary birefringence for measurement. A transmission spectrum shift corresponding to the measured mechanical load with a high sensitivity of 0.519 nm N −1 mm −1 is achieved. The proposed load sensor is also temperature-insensitive due to ultralow thermal dependence of the PCF.