Fei Yedeng, Xu Yin, Dong Yue, Zhang Bo, Ni Yi
Appl Opt. 2023 Aug 20;62(24):6499-6506. doi: 10.1364/AO.496942.
On-chip polarization management components play a critical role in tackling polarization dependence in the lithium-niobate-on-insulator (LNOI) platform. In this work, we proposed a reconfigurable TE-pass polarizer based on optical phase change material (GST) and the LNOI wafer. The key region is formed by a hybrid GST- layer symmetrically deposited atop the centerline of the LNOI waveguide along the propagation direction where the GST is sandwiched in the middle of the layer. Whether the polarizer will take effect depends on the phase states of the GST layer and the graphene and aluminum oxide layers are coated atop the - layer as the microheater to control the conversion of phase states. The proposed device length is 7.5 µm with an insertion loss (IL)=0.22 dB and extinction ratio (ER)=32.8 dB at the wavelength of 1550 nm. Moreover, it also has a high ER (>25 ) and a low IL (<0.5 ) in the operating bandwidth of 200 nm. Such a high-performance TE-pass polarizer paves a new way for applications of photonics integrated circuits.
片上偏振管理组件在解决绝缘体上铌酸锂（LNOI）平台中的偏振依赖性方面起着关键作用。在这项工作中，我们提出了一种基于光学相变材料（GST）和LNOI晶圆的可重构TE模式传输偏振器。关键区域由一层混合GST层沿LNOI波导中心线的传播方向对称沉积形成，其中GST夹在该层中间。偏振器是否起作用取决于GST层的相位状态，并且在该层顶部涂覆石墨烯和氧化铝层作为微加热器来控制相位状态的转换。所提出的器件长度为7.5微米，在1550纳米波长处插入损耗（IL）=0.22分贝，消光比（ER）=32.8分贝。此外，在200纳米的工作带宽内它还具有高消光比（>25）和低插入损耗（<0.5）。这种高性能的TE模式传输偏振器为光子集成电路的应用开辟了一条新途径。
