Tunable a temperature-dependent GST-based metamaterial absorber for switching and sensing applications

The development of temperature-sensitive tunable metamaterials based on GST particles is one of the hot topics. These metamaterials have rich resonance properties and can be used in communication, optical control, coding, and other fields. However, it is still elusive how to achieve the tunability of metamaterials based on GST particles while maintaining the original resonance performance. In this paper, a tunable Terahertz (THz) metamaterial based on GST particles is verified and measured, which can maintain the original resonances with temperature increasing. Two absorption peaks (P1: 86% at 1.98 THz, P2: 51% at 5.88 THz) and a valley (V1) are achieved by this metamaterial at room temperature. The P1, P2, and V1 of the samples are temperature-sensitive, which are shifted to lower frequencies with temperature increasing. The maximum FOM value is 7651, and the maximum S value is 2190. Moreover, the resonance position of the P2 is always covered by the V1 with the temperature increasing. Therefore, this proposed temperature-sensitive tunable metamaterial realizes the absorption window conversion between P2 peak (or “ON”) and V1 valley (or “OFF”). This proposed metamaterial can be applied to crystallinity sensing.