Department of Physics, National Chung Hsing University, 145, Xingda Rd., Taichung, 402, Taiwan, R.O.C.
Department of Physics, National Chung Hsing University, 145, Xingda Rd., Taichung, 402, Taiwan, R.O.C..
Sci Rep. 2017 Jul 3;7(1):4531. doi: 10.1038/s41598-017-05019-3.
We propose a polarization beam splitter (PBS) with a footprint of only 600 × 790 nm operating at a wavelength of λ = 1550 nm, which is the smallest PBS ever demonstrated. This device uses CMOS-compatible materials, namely, silicon and silica. The present PBS comprises two Si waveguides with different geometrical aspect ratios adjoined side-by-side, which separates the transverse-electric (TE) and transverse-magnetic (TM) modes without relying on an additional coupling region. The designed PBS achieves a polarization extinction ratio of approximately 25 dB for both modes and insertion losses of approximately 0.87 and 1.09 dB for the TE and TM polarizations, respectively. Over a wide bandwidth of 150 nm (from λ = 1475-1625 nm), a high polarization extinction ratio (greater than 20 dB) and a low inversion loss (lower than 1.3 dB) can be obtained. The proposed PBS allows for geometrical errors of ±15 nm while maintaining a polarization extinction ratio of >20 dB and inversion losses of >1.1 and 1.3 dB for the TE and TM modes, respectively. With the submicron footprint, the reported PBS may be able to be used in high-density photonic integrated circuits and nanophotonic devices.
我们提出了一种偏振分光器 (PBS)，其占地面积仅为 600×790nm，工作波长为 λ=1550nm，这是迄今为止最小的 PBS。该器件使用与 CMOS 兼容的材料，即硅和二氧化硅。目前的 PBS 由两个具有不同几何纵横比的 Si 波导并排连接而成，无需额外的耦合区域即可分离横电 (TE) 和横磁 (TM) 模式。设计的 PBS 对两种模式的偏振消光比约为 25dB，TE 和 TM 偏振的插入损耗分别约为 0.87 和 1.09dB。在 150nm 的宽带宽范围内（从 λ=1475-1625nm），可以获得高偏振消光比（大于 20dB）和低反转损耗（小于 1.3dB）。该 PBS 允许 ±15nm 的几何误差，同时保持 TE 和 TM 模式的偏振消光比大于 20dB，反转损耗分别大于 1.1 和 1.3dB。由于其亚微米级的占地面积，所报道的 PBS 可能能够用于高密度光子集成电路和纳米光子器件。
