Passive temperature sensor tag based on quasi-BIC

In this work, a highly sensitive temperature sensor based on bound states in the continuum (BIC) was proposed. A ceramic resonator with a half-cylindrical shape placed above a ground plane and designed to support high-quality factor supercavity modes. Experimentally, the sensor has been demonstrated to operate in a wide temperature range, from 25 to 105 ºC, with a resolution of 0.2 °C. The sensor's high-precision performance is based on the use of high-quality ferroelectric ceramics capable of supporting the confined modes with a high quality factor of more than 1000.