Liu Xinyu, Liu Dajian, Dai Daoxin
Opt Express. 2021 Jan 18;29(2):2720-2726. doi: 10.1364/OE.403932.
A silicon-based polarizing beam splitter (PBS) working at the 2 μm wavelength band is proposed and demonstrated experimentally by using a bent directional coupler assisted with a nano-slot waveguide. The nano-slot width is chosen as 180 nm so that the present PBS can be fabricated with MPW foundries. In theory, the designed PBS has extinction ratios (ERs) of >15 dB and >30 dB for TM- and TE- polarizations in the wavelength range of 1825-2020 nm, respectively. For the fabricated PBS, the excess losses (ELs) are low (∼0.5 dB) while the measured results show the ERs are >15 dB and >20 dB for TM- and TE-polarizations in the wavelength band of 1860-1980 nm.
提出了一种基于硅的偏振分束器（PBS），其工作在2μm波长波段，并通过使用辅助有纳米狭缝波导的弯曲定向耦合器进行了实验演示。纳米狭缝宽度选择为180nm，以便可以采用多项目晶圆代工工艺制造当前的PBS。理论上，所设计的PBS在1825 - 2020nm波长范围内，对于TM偏振和TE偏振的消光比（ER）分别大于15dB和大于30dB。对于制造的PBS，过量损耗（EL）较低（约0.5dB），而测量结果表明，在1860 - 1980nm波段内，对于TM偏振和TE偏振的ER分别大于15dB和大于20dB。
