Benefiting from the sensitive response to the change of surrounding environment, localized surface plasmon resonance sensors have wide applications for the detection of bio-/chemical species. Traditionally, the sensitivity research of localized surface plasmon resonance sensors mainly focused on the morphologies and materials of sensor structures. Instead, the effect of environmental refractive index on sensitivity of a gold (Au) nanoparticle sensor is theoretically investigated in this work. The results show that when few free targets are adjacent to the sensor, a better sensing performance can be achieved as the refractive index increases from 1.00 to 1.10. However, when a target layer is closely covered on the Au nanoparticle, a 0.1 decrease in environmental refractive index can lead to a significant improvement in sensitivity. The similar results can be also obtained on a silver (Ag) nanoparticle. This work provides new understandings for advanced sensing applications of surface plasmon resonance sensors.

中文翻译：

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金、银纳米粒子在不同周围环境下的折射率传感性能

得益于对周围环境变化的敏感响应，局域表面等离子体共振传感器在生物/化学物质的检测中具有广泛的应用。传统上，局域表面等离子体共振传感器的灵敏度研究主要集中在传感器结构的形貌和材料方面。相反，本工作从理论上研究了环境折射率对金 (Au) 纳米粒子传感器灵敏度的影响。结果表明，当传感器附近自由目标较少时，随着折射率从1.00增加到1.10，可以获得更好的传感性能。然而，当目标层紧密覆盖在 Au 纳米粒子上时，环境折射率降低 0.1 即可导致灵敏度显着提高。在银（Ag）纳米颗粒上也可以获得类似的结果。这项工作为表面等离子体共振传感器的先进传感应用提供了新的理解。