A temperature sensor based on optical microfiber knot resonator

A type of compact temperature sensor based on microfiber knot resonator is proposed and demonstrated experimentally. The microfiber knot, which is assembled by two fiber probes, is placed on a plate glass substrate and coated with low-index polymer to keep the system robust. Sensitivities of this kind of temperature sensor as 0.27 nm/degrees C in heating process (when temperature ranges from 28 to 140 degrees C) and -0.28 nm/degrees C in cooling process (when temperature ranges from 135 to 25 degrees C) are obtained. Temperature resolution of 0.5 degrees C is demonstrated and higher resolution is predicted with a high-resolution spectrometer. (C) 2009 Elsevier B.V. All rights reserved.