Temperature Sensing in Nuclear Facilities: Application of the Phase Change Effect of Chalcogenide Glasses

Temperature sensing is an integral part of any nuclear reactor facilities. However, high radiation and temperature degrade the sensing materials which in turn makes the sensors less reliable. In this paper, chalcogenide glasses are proposed as temperature sensing materials for reactor facilities. Chalcogenide glasses go through amorphous to crystalline phase transformation when heated up to their crystallization temperature. This phase transition changes both the electrical and optical properties of the chalcogenide glasses. They are amorphous in nature and radiation hard due to their specific electronic structure and high defect density. Difference in reflected power at 1310 nm and 1550 nm wavelengths as a function of temperature, from chalcogenide glass-silica interface can be utilized to measure temperature and this effect is applied in the device presented in this paper. A review of the radiation hardness and a study of thermally induced change in optical properties of Ge-containing chalcogenide glasses along with a device architecture are presented as a method for temperature monitoring in nuclear facilities.