Bound states in the continuum (BICs) are widely studied for their ability to confine light, produce sharp resonances for sensing applications and serve as avenues for lasing action with topological characteristics. Primarily, the formation of BICs in periodic photonic band gap structures are driven by symmetry incompatibility; structural manipulation or variation of incidence angle from incoming light. In this work, we report two modalities for driving the formation of BICs in terahertz metasurfaces. At normal incidence, we experimentally confirm polarization driven symmetry-protected BICs by the variation of the linear polarization state of light. In addition, we demonstrate through strong coupling of two radiative modes the formation of capacitively-driven Freidrich-Wintgen BICs, exotic modes which occur in off-Γ points not accessible by symmetry-protected BICs. The capacitance-mediated strong coupling at 0° polarization is verified to have a normalized coupling strength ratio of 4.17% obtained by the Jaynes-Cummings model. Furthermore, when the polarization angle is varied from 0° to 90° (0° ≤ ϕ < 90°), the Freidrich-Wintgen BIC is modulated until it is completely switched off at 90°.

连续态（BIC）的束缚态因其限制光，在传感应用中产生尖锐共振以及充当具有拓扑特性的激射作用的途径而被广泛研究。首先，周期性光子带隙结构中BIC的形成是由对称不相容性驱动的。结构操纵或入射光的入射角变化。在这项工作中，我们报告了两种驱动太赫兹超表面形成BIC的方式。在法向入射时，我们通过光的线性偏振态的变化实验确定偏振驱动的对称保护BIC。此外，我们通过两种辐射模式的强耦合说明了电容驱动的Freidrich-Wintgen BIC的形成，这是非Γ发生的奇异模式受对称保护的BIC无法访问的点。验证了通过Jaynes-Cummings模型获得的0°极化下的电容介导的强耦合具有4.17％的归一化耦合强度比。此外，当偏振角从0°到90°变化（0°≤ φ  <90°）时，Freidrich-Wintgen BIC进行调制，直到它是在90℃完全关闭。