All-fiber-optic temperature sensor based on reduced graphene oxide

We demonstrate a novel all-fiber-optic temperature sensor based on a reduced graphene oxide (rGO) film coated onto a side-polished fiber (SPF). Significantly enhanced interaction between the propagating light and the rGO film can be obtained via strong evanescent field of the SPF. The strong light-graphene interaction results in temperature sensing with a maximum optical power variation of 11.3 dB in the SPF experimentally. The novel temperature fiber sensor has a linear correlation coefficient of 99.4%, a sensitivity of 0.134 dB degrees C-1, a precision of better than 0.03 degrees C, and a response speed of better than 0.0228 degrees C s(-1). Such an rGO-based all-fiber-optic temperature sensor is easy to fabricate, is compatible with fiber-optic systems, and possesses high potentiality in photonics applications such as all-fiber-optic temperature sensing networks.