Liquid metal-based metamaterial with high-temperature sensitivity: Design and computational study

Abstract

Abstract This article proposes a metamaterial-based temperature sensor with high sensitivity using the thermally tunable liquid metal of mercury. The response of the metamaterial at different temperatures is theoretically investigated. In the merit of the temperature-sensitive thermal expanding of the embedded mercury resonant structure, different absorption peak frequencies can be observed at different temperatures, which enables the proposed metamaterial capability of temperature sensing. The numerical simulations show that the temperature sensitivity of the proposed sensor can reach up to 27.64 MHz/°C within the range of 0–21.8°C. The calculated electric field and surface current distributions illustrate that the high sensitivity is originated from the dual-dipole mode of the resonant structure. Meanwhile, the dependence of the structural dimensions on temperature sensitivity is discussed to optimize the sensor design. The proposed strategy paves a new way for developing temperature sensors with high sensitivity.