Liu Wanwan, Chen Yifu, Hu Xin, Wen Long, Jin Lin, Su Qiang, Chen Qin
Appl Opt. 2017 Jun 1;56(16):4861-4867. doi: 10.1364/AO.56.004861.
Non-metallic plasmonic materials have recently attracted research interest due to their adjustable plasmonic material properties and the potential low loss, which is important to plasmonic waveguides with ultrahigh mode confinement. In this paper, we analyzed the mode properties of four types of plasmonic waveguides based on noble metals, aluminum-zinc-oxide (AZO), and TiN, where the propagation length and mode size are chosen to compare the figures of merit. It is found that AZO has the smallest imaginary part of permittivity in the near-infrared region, while AZO waveguides have propagation lengths comparable to those of Cu waveguides but shorter than those of Au and Ag waveguides. Furthermore, due to the larger real part of permittivities, the mode sizes of the AZO and TiN waveguides are smaller than those of the metal waveguides, in particular, for the insulator-metal-insulator waveguide and dielectric-loaded plasmonic waveguide. AZO/ZnO films with tunable carrier density between 1.8×10/cm and 8.6×10/cm were grown by pulsed-laser deposition. Metal-like properties, i.e., negative real part of permittivity around 1550 nm, were observed, predicting an interesting candidate in the plasmonic optical interconnect.
非金属等离子体材料因其可调节的等离子体材料特性以及潜在的低损耗，近来引起了研究兴趣，这对于具有超高模式限制的等离子体波导而言至关重要。在本文中，我们分析了基于贵金属、铝锌氧化物（AZO）和氮化钛（TiN）的四种类型等离子体波导的模式特性，其中选择传播长度和模式尺寸来比较品质因数。结果发现，AZO在近红外区域具有最小的介电常数虚部，而AZO波导的传播长度与铜波导相当，但比金和银波导短。此外，由于介电常数实部较大，AZO和TiN波导的模式尺寸比金属波导小，特别是对于绝缘体 - 金属 - 绝缘体波导和介质加载等离子体波导。通过脉冲激光沉积生长了载流子密度在1.8×10/cm至8.6×10/cm之间可调的AZO/ZnO薄膜。观察到类金属特性，即在1550 nm附近介电常数实部为负，这预示着其在等离子体光互连方面是一个有趣的候选材料。
