Petropoulou Afroditi, Drikakis Dimitris, Riziotis Christos
Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 116 35 Athens, Greece.
Department of Informatics and Telecommunications, University of Peloponnese, 22100 Tripolis, Greece.
Materials (Basel). 2019 Jun 19;12(12):1969. doi: 10.3390/ma12121969.
Multicomponent optical fibers with incorporated metals are promising photonic platforms for engineering of tailored plasmonic structures by laser micromachining or thermal processing. It has been observed that during thermal processing microfluidic phenomena lead to the formation of embedded micro- and nanostructures and spheres, thus triggering the technological motivation for their theoretical investigation, especially in the practical case of noble metal/glass composites that have not yet been investigated. Implemented microwires of gold core and glass cladding, recently studied experimentally, are considered as a reference validation platform. The Plateau-Rayleigh instability in such hybrid fibers is theoretically investigated by inducing surface tension perturbations and by comparing them to the Tomotika instability theory. The continuous-core breakup time was calculated via Finite Element Method (FEM) simulations for different temperatures and was found to be considerably higher to Tomotika's model, while the final sphere diameter is a linear function of the initial core radius. Different sinusoidal perturbation parameters were considered, showing significant impact in the characteristics of formed spherical features. The theoretical results were in close agreement with previous experimental observations expected to assist in the understanding of the processes involved, providing insight into the engineering of fibers, both in the initial drawing process and post processing.
含有金属的多组分光纤是很有前景的光子平台，可通过激光微加工或热处理来设计定制的等离子体结构。据观察，在热处理过程中，微流体现象会导致嵌入式微纳结构和球体的形成，从而引发对其进行理论研究的技术动机，特别是在尚未研究的贵金属/玻璃复合材料的实际情况中。最近通过实验研究的金芯玻璃包层微丝被视为一个参考验证平台。通过引入表面张力扰动并将其与友田 instability 理论进行比较，对这种混合光纤中的普拉托 - 瑞利不稳定性进行了理论研究。通过有限元方法（FEM）模拟计算了不同温度下连续芯的破裂时间，发现其比友田模型的结果高得多，而最终球体直径是初始芯半径的线性函数。考虑了不同的正弦扰动参数，结果表明其对形成的球形特征的特性有显著影响。理论结果与先前的实验观察结果密切一致，有望有助于理解所涉及的过程，为光纤在初始拉伸过程和后处理过程中的工程设计提供见解。
