Abstract Effective dynamic modulation of visible light properties has been significantly desired for advanced imaging and sensing technologies. In particular, phase-change materials have attracted much attention as active material platforms owing to their broadband tunability of optical dielectric functions induced by the temperature-dependent phase-changes. However, their uses for visible light modulators are still limited to meet multi-objective high performance owing to the low material quality factor and active tunability in the visible regime. Here, a design strategy of phase-change metafilm absorber is demonstrated by making the use of the material drawbacks and extending design degree of freedom. By engineering tunability of effective anisotropic permittivity tensor of VO2-Ag metafilm around near-unity absorption conditions, strong dynamic modulation of reflection wave is achieved with near-unity modulation depth at desired wavelength regions without sacrificing bandwidth and efficiency. By leveraging effective medium theory of metamaterial and coupled mode theory, the intuitive design rules and theoretical backgrounds are suggested. It is also noteworthy that the dynamic optical applications of intensity modulation, coloring, and polarization rotation are enabled in a single device. By virtue of ultrathin flat configuration of a metafilm absorber, design extensibility of reflection spectrum is also verified. It is envisioned that our simple and powerful strategy would play a robust role in development of miniaturized light modulating pixels and a variety of photonic and optoelectronic applications.

中文翻译：

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动态相变超薄膜吸收器，用于对可见光进行强设计师调制

摘要 先进的成像和传感技术非常需要对可见光特性进行有效的动态调制。特别是，相变材料作为活性材料平台备受关注，因为它们具有由温度相关的相变引起的光介电函数的宽带可调性。然而，由于材料质量因数低和可见光范围内的主动可调性，它们在可见光调制器中的应用仍然受限于满足多目标高性能。在这里，通过利用材料缺点和扩展设计自由度，展示了相变超薄膜吸收器的设计策略。通过在接近统一吸收条件下对 VO2-Ag 超薄膜的有效各向异性介电常数张量进行工程可调，在不牺牲带宽和效率的情况下，在所需波长区域以接近统一的调制深度实现了反射波的强动态调制。利用超材料的有效介质理论和耦合模式理论，提出了直观的设计规则和理论背景。还值得注意的是，强度调制、着色和偏振旋转的动态光学应用可以在单个设备中实现。凭借超薄平面吸收器的超薄配置，反射光谱的设计扩展性也得到了验证。可以设想，我们简单而强大的策略将在微型光调制像素的开发和各种光子和光电应用的开发中发挥强大的作用。