Liu Changxu, Wu Tong, Lalanne Philippe, Maier Stefan A
Centre for Metamaterial Research & Innovation, Department of Engineering, University of Exeter, Exeter EX4 4QF, United Kingdom.
LP2N, Institut d'Optique Graduate School, CNRS, Université de Bordeaux, Talence 33400, France.
Nano Lett. 2024 Apr 17;24(15):4641-4648. doi: 10.1021/acs.nanolett.4c00810. Epub 2024 Apr 5.
The intrinsic properties of materials play a substantial role in light-matter interactions, impacting both bulk metals and nanostructures. While plasmonic nanostructures exhibit strong interactions with photons via plasmon resonances, achieving efficient light absorption/scattering in other transition metals remains a challenge, impeding various applications related to optoelectronics, chemistry, and energy harvesting. Here, we propose a universal strategy to enhance light-matter interaction, through introducing voids onto the surface of metallic nanoparticles. This strategy spans nine metals including those traditionally considered optically inactive. The absorption cross section of void-filled nanoparticles surpasses the value of plasmonic (Ag/Au) counterparts with tunable resonance peaks across a broad spectral range. Notably, this enhancement is achieved under arbitrary polarizations and varied particle sizes and in the presence of geometric disorder, highlighting the universal adaptability. Our strategy holds promise for inspiring emerging devices in photocatalysis, bioimaging, optical sensing, and beyond, particularly when metals other than gold or silver are preferred.
材料的固有特性在光与物质的相互作用中起着重要作用，对块状金属和纳米结构均有影响。虽然等离子体纳米结构通过等离子体共振与光子表现出强烈的相互作用，但在其他过渡金属中实现高效的光吸收/散射仍然是一个挑战，这阻碍了与光电子学、化学和能量收集相关的各种应用。在此，我们提出了一种通用策略，通过在金属纳米颗粒表面引入空隙来增强光与物质的相互作用。该策略涵盖九种金属，包括那些传统上被认为光学惰性的金属。填充空隙的纳米颗粒的吸收截面超过了等离子体（银/金）对应物的值，在很宽的光谱范围内具有可调谐的共振峰。值得注意的是，这种增强在任意偏振、不同粒径以及存在几何无序的情况下都能实现，突出了其普遍适用性。我们的策略有望激发光催化、生物成像、光学传感等领域的新兴器件，特别是在更倾向于使用金或银以外的金属时。
