An ultrathin all-dielectric terahertz metamaterial with quasi-BIC induced angular dispersion

) supporting layer with thicknesses of 5 μm and 2 μm, respectively. The UATM exhibits quasi-bound state in the continuum (quasi-BIC) modes related to the tilt angle and period parameters. Moreover, due to the strong electromagnetic field near the interfaces and large interaction area, the UATM exhibits a high refractive index sensitivity exceeding 1.00 THz per RIU. Furthermore, at oblique incident angles ranging from 0° to 25°, the resonant quality factor (Q-factor) of the UATM remains higher than 100, and the sensitivities to the incident angle are 22.53 and 26.17 GHz per degree with a linear range of 0.498 THz and 0.438 THz, respectively. These properties indicate the potential applications of the UATM in high sensitivity biochemical sensing and multifunctional narrowband filtering fields.