In this article we experimentally and theoretically study the plasmonic properties of discrete copper nanocups fabricated by magnetron sputtering on ordered, non-close-packed colloidal templates. Wide tunability of the main plasmon resonance peak between 900 and 1500 nm, extending the typical plasmon resonance range previously reported for other copper nanostructures between 600 and 1000 nm, is achieved by varying shell thickness and particle size in the colloidal template. The nature of the plasmon resonance peaks is revealed from calculated charge maps and electromagnetic field intensity maps. Good agreements are found between experimental and calculated extinction spectra, which validates the geometry model and suggests that the nanocups have a well-defined shape. The main plasmon resonance peak exhibits a minor red-shift and attenuation after 3 days of oxidation and eventually stabilizes after 13 days. We also demonstrate that a potentially useful optical material that blocks near-infrared but transmits visible light can be constructed by mixing copper nanocups of three different sizes at appropriate ratios.

中文翻译：

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模板辅助磁控溅射制备的近红外等离子铜纳米杯

在本文中，我们从实验和理论上研究了磁控溅射在有序，非密排胶体模板上通过磁控溅射制备的离散铜纳米杯的等离子体特性。通过改变胶体模板的壳厚度和粒径，可以实现900-1500 nm之间的主要等离振子共振峰的宽可调性，扩展了先前报道的600-1000 nm之间其他铜纳米结构的典型等离激元共振范围。从计算出的电荷图和电磁场强度图可以看出等离振子共振峰的性质。在实验和计算的消光光谱之间找到了很好的一致性，这验证了几何模型并表明纳米杯具有明确定义的形状。等离子体的主共振峰在氧化3天后表现出较小的红移和衰减，并在13天后稳定下来。我们还证明，可以通过以适当的比例混合三种不同尺寸的铜纳米杯来构造一种潜在的有用的光学材料，该材料可以阻挡近红外光并透射可见光。