This article presents the new nanoplasmonic branchline coupler (BLC) by using an edge coupled coplanar waveguide (CPW) with a finite length suspended backed conductor. The proposed coupler is designed by using the theoretical transmission line (TL) method, which is established based on the basic characteristics of the related CPW structures. For this purpose, the normalized propagation constant, propagation length, and characteristic impedance of the conductor backed coplanar waveguide (CBCPW) structure are studied and analyzed by applying a fullwave analysis using CAD simulation software tool CST microwave studio suite. Mainly, the coupling coefficient of the BLC can be controlled by changing the length of the backed conductor. In this article, the BLC is designed and analyzed by using a finite length backed conductor based on the theoretical TL method at a 3-dB coupling coefficient. This newly designed coupler can operate at two arbitrary optical frequency bands (O-band and L-band). Hence, it allows us to exchange many other couplers with their narrow bandwidths using this branchline coupler for subwavelength nanoscale wireless network applications and photonic integrated circuits (PICs).

中文翻译：

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用于亚波长无线网络的纳米等离子体分支线耦合器


本文介绍了一种新型纳米等离子体分支线耦合器 (BLC)，该耦合器使用具有有限长度悬挂背衬导体的边缘耦合共面波导 (CPW)。所提出的耦合器是利用理论传输线（TL）方法进行设计的，该方法是根据相关共面波导结构的基本特征建立的。为此，利用 CAD 仿真软件工具 CST 微波工作室套件进行全波分析，研究和分析了背导体共面波导 (CBCPW) 结构的归一化传播常数、传播长度和特性阻抗。主要可以通过改变背衬导体的长度来控制BLC的耦合系数。在本文中，基于理论 TL 方法，使用有限长度背衬导体在 3 dB 耦合系数下设计和分析了 BLC。这种新设计的耦合器可以在两个任意光频段（O 波段和 L 波段）下工作。因此，它允许我们使用这种支线耦合器来交换许多其他窄带宽耦合器，用于亚波长纳米级无线网络应用和光子集成电路（PIC）。