Ensuring a good trade-off between high-quality factor (Q-factor) and polarization independency is a key challenge for designing practicable terahertz metamaterial devices. We propose a symmetric composite aluminum-structured metamaterial absorber to achieve high Q-factor beyond 80 and near-unity absorbance of arbitrary polarization waves in the terahertz regime. Ultrahigh Q-factor reaches 84, and polarization-independent absorption is as high as 99% for resonant frequency tuning from 7.58 to 8.97 THz, covering 14% of the standard THz gap. The geometric effect of the symmetric sublattice on resonant frequency tuning is analyzed. The large Q-factor and strong absorption by oblique incidence is discussed. Designed high-Q metamaterial perfect absorber has various applications, including terahertz hyperspectral imaging, filtering, and sensing.

在设计实用的太赫兹超材料器件时，确保高质量因子（Q因子）和极化独立性之间的良好折衷是一项关键挑战。我们提出一种对称的复合铝结构超材料吸收体，以在太赫兹范围内实现超过80的高Q值和任意极化波的近统一吸收。超高Q因子达到84，并且从7.58至8.97 THz的谐振频率调谐，偏振无关的吸收高达99％，覆盖了标准THz间隙的14％。分析了对称子晶格对谐振频率调谐的几何影响。讨论了大Q因子和斜入射强吸收。设计高Q值 超材料完美吸收体具有多种应用，包括太赫兹高光谱成像，滤波和传感。