Abstract Reconfigurable plasmonics is driving an extensive quest for active materials that can support a controllable modulation of their optical properties for dynamically tunable plasmonic structures. Here, polymorphic gallium (Ga) is demonstrated to be a very promising candidate for adaptive plasmonics and reconfigurable photonics applications. The Ga sp-metal is widely known as a liquid metal at room temperature. In addition to the many other compelling attributes of nanostructured Ga, including minimal oxidation and biocompatibility, its six phases have varying degrees of metallic character, providing a wide gamut of electrical conductivity and optical behavior tunability. Here, the dielectric function of the several Ga phases is introduced and correlated with their respective electronic structures. The key conditions for optimal optical modulation and switching for each Ga phase are evaluated. Additionally, we provide a comparison of Ga with other more common phase-change materials, showing better performance of Ga at optical frequencies. Furthermore, we first report, to the best of our knowledge, the optical properties of liquid Ga in the terahertz (THz) range showing its broad plasmonic tunability from ultraviolet to visible-infrared and down to the THz regime. Finally, we provide both computational and experimental evidence of extension of Ga polymorphism to bidimensional two-dimensional (2D) gallenene, paving the way to new bidimensional reconfigurable plasmonic platforms.

中文翻译：

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用于光子纳米结构中主动共振调谐的多晶镓：从块状镓到二维 (2D) 镓烯

摘要 可重构等离子体正在推动对活性材料的广泛探索，这些材料可以支持对其光学特性的可控调制，以实现动态可调谐等离子体结构。在这里，多态镓 (Ga) 被证明是自适应等离子体和可重构光子学应用的非常有前途的候选材料。Ga sp-金属在室温下作为液态金属而广为人知。除了纳米结构 Ga 的许多其他引人注目的属性，包括最小的氧化和生物相容性，它的六相具有不同程度的金属特性，提供广泛的导电性和光学行为可调性。在这里，介绍了几种 Ga 相的介电函数，并与它们各自的电子结构相关联。评估了每个 Ga 相的最佳光调制和开关的关键条件。此外，我们提供了 Ga 与其他更常见的相变材料的比较，显示了 Ga 在光学频率下的更好性能。此外，据我们所知，我们首先报告了太赫兹 (THz) 范围内液态 Ga 的光学特性，显示了其从紫外到可见光-红外以及低至太赫兹范围的广泛等离子体可调性。最后，我们提供了 Ga 多态性扩展到二维二维 (2D) gallenene 的计算和实验证据，为新的二维可重构等离子体平台铺平了道路。Ga 在光频率下表现出更好的性能。此外，据我们所知，我们首先报告了太赫兹 (THz) 范围内液态 Ga 的光学特性，显示了其从紫外到可见光-红外以及低至太赫兹范围的广泛等离子体可调性。最后，我们提供了 Ga 多态性扩展到二维二维 (2D) gallenene 的计算和实验证据，为新的二维可重构等离子体平台铺平了道路。Ga 在光频率下表现出更好的性能。此外，据我们所知，我们首先报告了太赫兹 (THz) 范围内液态 Ga 的光学特性，显示了其从紫外到可见光-红外以及低至太赫兹范围的广泛等离子体可调性。最后，我们提供了 Ga 多态性扩展到二维二维 (2D) gallenene 的计算和实验证据，为新的二维可重构等离子体平台铺平了道路。