Distributed cryogenic temperature sensing through Brillouin optical frequency-domain analysis

We present the results of an experimental campaign aimed at demonstrating the use of a distributed optical fiber sensor based on Brillouin scattering in static and dynamic temperature measurements at cryogenic temperatures (? 84 K). The experimental results, obtained through Brillouin Optical Frequency-Domain Analysis (BOFDA) at a spatial resolution of 16 mm, are compared with temperature measurements using thermocouples and fiber Bragg gratings. The distributed sensor is able to capture local temperature variations of ? 2 °C at an acquisition rate of 1 Hz.