Nath Jyoti Prasad, Saxena Geetika Jain, Sharma Enakshi K
Appl Opt. 2023 Aug 20;62(24):6380-6388. doi: 10.1364/AO.495046.
A compact wavelength and mode division (de)multiplexer is proposed for multiplexing a total of eight guided TE modes of a 220 nm thick silicon-on-insulator waveguide with input channels at two wavelengths of 1.55 and 2 µm for wavelength division multiplexing. The (de)multiplexer is composed of four sequentially arranged sections with bus waveguides of increasing widths. The first section uses an asymmetric directional coupler to couple one TE mode at 1.55 µm, while each of the next three sections consists of two collocated directional couplers to simultaneously couple two TE modes of the bus waveguide, one at each wavelength of 1.55 and 2 µm. Three linear adiabatic tapers are designed to connect the consecutive bus waveguides. The fundamental TE mode of the bus waveguide at 1.55 or 2 µm is coupled by using another adiabatic taper from a single-mode input waveguide. The simulation results show that over a broad bandwidth of >100 the insertion loss and crosstalk for both wavelength bands is <1.15 and <-27 , respectively. In addition, a compact device footprint with a total coupling length of ∼61µ is achieved due to the use of collocated directional couplers in three sections.
本文提出了一种紧凑型波长和模式分束复用器，用于复用220nm厚的绝缘体上硅波导中的总共八个TE导模，输入通道位于1.55μm和2μm两个波长处，用于波分复用。该分束复用器由四个依次排列的部分组成，各部分的总线波导宽度逐渐增加。第一部分使用非对称定向耦合器来耦合一个1.55μm的TE模式，而后三个部分中的每一部分均由两个并置的定向耦合器组成，用于同时耦合总线波导的两个TE模式，一个位于1.55μm波长处，另一个位于2μm波长处。设计了三个线性绝热渐变区来连接连续的总线波导。1.55μm或2μm处总线波导的基模TE通过另一个绝热渐变区从单模输入波导进行耦合。仿真结果表明，在大于100nm的宽带宽内，两个波段的插入损耗均<1.15dB，串扰均<-27dB。此外，由于在三个部分中使用了并置的定向耦合器，实现了总耦合长度约为61μm的紧凑设备尺寸。
