Based on the phase transition properties of vanadium dioxide (VO₂), a metamaterial device is designed in this paper, which can achieve multiple switchable functions. When VO₂ is in the metallic state, the proposed device can realize broadband absorption with peak absorbance more than 90 % in the frequency range of 2.40–6.73 THz and broadband linear polarization conversion (LPC) with polarization conversion ratio (PCR) greater than 90% in the range of 1.80–4.21 THz, respectively, depending on whether the incidence of terahertz (THz) electromagnetic (EM) wave is from top side or bottom side. When VO₂ is in the insulated state, the proposed device can achieve LPC of half-reflection and half-transmission (HRHT) and transmissive linear-to-circular (LTC) polarization conversion. The study in this paper has guiding significance in the design of THz metamaterial devices with multiple functions.

本文基于二氧化钒（VO ₂ ）的相变特性，设计了一种超材料器件，可以实现多种可切换功能。当VO ₂处于金属态时，该器件可以在2.40-6.73 THz频率范围内实现峰值吸光度超过90%的宽带吸收和偏振转换比（PCR）大于90的宽带线性偏振转换（LPC） % 分别在 1.80–4.21 THz 范围内，具体取决于太赫兹 (THz) 电磁 (EM) 波是从顶部还是底部入射。当VO ₂处于绝缘状态时，所提出的器件可以实现半反射半透射(HRHT)的LPC和透射式线圆(LTC)偏振转换。本文的研究对于多功能太赫兹超材料器件的设计具有指导意义。