Realization of a sensitivity multi-band tunable sensor through modulating the phase change of Ge2Sb2Te5

Abstract

Metamaterials with active modulation properties have broad application prospects. Here, we demonstrate a metamaterial with a structured phase-change alloy Ge2Sb2Te5 (GST) disk array, which supports the active tunability by changing crystallinity. At room temperature, two transmission peaks (0.642 at 6.21 THz, 0.659 at 10.96 THz) are achieved based on bright-dark mode coupling. In experiments, the P1 peak is enhanced by reducing the vertical distance of GST disks, while the P2 peak is enhanced by reducing the horizontal distance. In further experiments, as the crystallinity increases, the resonance position of the P1 peak is replaced by the valley V1, thereby realizing the “OPEN” and “CLOSE” of the transmission window of the metamaterial. This metamaterial shows a new direction to achieve active optics devices or sensors.