High-resolution temperature sensor through measuring the frequency shift of single-frequency Erbium-doped fiber ring laser

Abstract

We propose a principle to achieve a high-resolution temperature sensor through measuring the central frequency shift in the single-frequency Erbium-doped fiber ring laser induced by the thermal drift via the optical heterodyne spectroscopy method. We achieve a temperature sensor with a sensitivity about 9.7 pm/°C and verify the detection accuracy through an experiment. Due to the narrow linewidth of the output singlefrequency signal and the high accuracy of the optical heterodyne spectroscopy method in measuring the frequency shift in the single-frequency ring laser, the temperature sensor can be employed to resolve a temperature drift up to ~5.5×10 -6 °C theoretically when the single-frequency ring laser has a linewidth of 1 kHz and 10-kHz frequency shift is achieved from the heterodyne spectra.