Purpose

This paper aims to study the sensitivity enhancement effect of the gold nanorod on fiber surface plasmon resonance (SPR) sensor. It proposes modeling the sensing effects of fiber SPR sensor decorated with metal nanoparticles. By using simulation and experiment, the sensitivity enhancement effect of the gold nanorod was studied and demonstrated.

Design/methodology/approach

The paper opted for an exploratory study using simulation approach of finite-difference time-domain. Specifically, the effect of ratios and aspect ratios of gold nanorod on sensing performance are investigated theoretically. Based on the mathematical models, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 were done to verify the sensitivity enhancement effect of the gold nanorod.

Findings

In conclusion, it is evident that with the increases of the aspect ratios, the sensing sensitivity of the refractive index increases first, then gradually stabilizes or decreases. After parameter optimization, the ratios and aspect ratios of gold nanorod are chosen to be 8 nm and 12.5, respectively, which makes the optimal refractive index sensitivity of 4465.53 nm/RIU be realized. In addition, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 verify the sensitivity enhancement effect of the gold nanorods.

Originality/value

This paper proposes and demonstrates a new method for the sensitivity enhancement of fiber SPR sensor. After parameter optimization, the maximum sensitivity of 4465.53 nm/RIU was achieved by using 8 nm gold nanorods with the aspect ratios of 12.5. To verify the sensitivity enhancement of the gold nanorods, the authors also did the validation experiments. The testing results indicated that after the decoration of the gold nanorods, the sensitivity of the sensing probe increases from 2190.57 nm/RIU to 2693.24 nm/RIU, which demonstrates the sensitivity enhancement effect of the gold nanorods.

中文翻译：

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金纳米棒增强光纤SPR传感器灵敏度的研究

目的

本文旨在研究金纳米棒对纤维表面等离子体共振（SPR）传感器的灵敏度增强效果。它建议对用金属纳米粒子装饰的光纤 SPR 传感器的传感效果进行建模。通过模拟和实验，对金纳米棒的增敏作用进行了研究和论证。

设计/方法/方法

论文选择了使用有限差分时域的模拟方法进行探索性研究。具体而言，从理论上研究了金纳米棒的比例和纵横比对传感性能的影响。基于数学模型，利用纵横比为5.1的金纳米棒进行验证实验，验证金纳米棒的增敏效果。

发现

综上所述，很明显，随着纵横比的增加，折射率的传感灵敏度先增加，然后逐渐稳定或降低。经过参数优化，金纳米棒的比例和纵横比分别选择为8 nm和12.5，实现了4465.53 nm/RIU的最佳折射率灵敏度。此外，使用纵横比为5.1的金纳米棒的验证实验验证了金纳米棒的灵敏度增强效果。

原创性/价值

本文提出并论证了一种提高光纤SPR传感器灵敏度的新方法。参数优化后，使用纵横比为12.5的8nm金纳米棒获得了4465.53nm/RIU的最大灵敏度。为了验证金纳米棒的灵敏度增强，作者还进行了验证实验。测试结果表明，金纳米棒修饰后，传感探针的灵敏度从2190.57 nm/RIU增加到2693.24 nm/RIU，证明了金纳米棒的灵敏度增强效果。