Polymer dependent acoustic mode coupling and Hooke's law spring constants in stacked gold nanoplates.
Polymer dependent acoustic mode coupling and Hooke's law spring constants in stacked gold nanoplates.
复制标题
DOI：
10.1063/5.0066661
复制
发表时间：
2021-10
期刊：
影响因子：
--
通讯作者：
Junzhong Wang;Mengying Li;Yiqi Jiang;Kuai Yu;G. Hartland;Guo Ping Wang
中科院分区：
文献类型：
--
作者：
Junzhong Wang;Mengying Li;Yiqi Jiang;Kuai Yu;G. Hartland;Guo Ping Wang
金属纳米粒子是优异的声谐振器，其振动光谱已被广泛研究。然而，不同纳米颗粒振动模式之间的耦合却很少被探索。例如，中间介质如何影响耦合强度尚不清楚。在这里，我们研究了不同的聚合物如何影响金纳米板-聚合物-金纳米板夹层结构中的耦合。使用单粒子泵探针光谱测量金纳米板呼吸模式之间的耦合，并通过实验确定聚合物依赖性耦合强度。声模耦合分析给出了聚合物的有效弹簧常数。还观察到堆叠的金纳米板的相对运动模式。该模式的频率与呼吸模式的耦合常数密切相关。使用耦合振荡器模型分析呼吸模式耦合和相对运动模式。该模型表明，这两种效应都可以使用聚合物的相同弹簧常数来描述。最后，我们提出了一种使用强耦合谐振器的新型质量平衡。我们证明谐振器的质量检测极限为几飞克。我们预计，对声谐振器中振动耦合的进一步了解将提高耦合强度并扩大其潜在应用。
Metal nanoparticles are excellent acoustic resonators and their vibrational spectroscopy has been widely investigated. However, the coupling between vibrational modes of different nanoparticles is less explored. For example, how the intervening medium affects the coupling strength is not known. Here, we investigate how different polymers affect coupling in Au nanoplate-polymer-Au nanoplate sandwich structures. The coupling between the breathing modes of the Au nanoplates was measured using single-particle pump-probe spectroscopy, and the polymer dependent coupling strength was determined experimentally. Analysis of the acoustic mode coupling gives the effective spring constant for the polymers. A relative motion mode was also observed for the stacked Au nanoplates. The frequency of this mode is strongly correlated with the coupling constant for the breathing modes. The breathing mode coupling and relative motion mode were analyzed using a coupled oscillator model. This model shows that both these effects can be described using the same spring constant for the polymer. Finally, we present a new type of mass balance using the strongly coupled resonators. We show that the resonators have a mass detection limit of a few femtograms. We envision that further understanding of the vibrational coupling in acoustic resonators will improve the coupling strength and expand their potential applications.