Polarization control is at the heart of high-capacity data optical communication systems, such as polarization-division multiplexers and Stokes vector modulation transmitters. Despite passive polarization control being mature, the realization of monolithically integrated polarization controllers and single longitudinal mode light sources, such as distributed-feedback (DFB) lasers, is of importance. In this research, we report an AlGaInAs multiple-quantum-well photonic integrated circuit device which can control the state of polarization of the output light source, consisting of a polarization mode converter (PMC), a differential phase shifter (DPS), and a sidewall grating DFB laser. We demonstrate an asymmetrical stepped-height ridge waveguide PMC to realize TE to TM polarization conversion and a symmetrical straight waveguide DPS to enable polarization rotation from approximately counterclockwise circular polarization to linear polarization. Based on the identical epitaxial layer scheme, all the PMC, DPS, and DFB lasers can be integrated monolithically using only a single step of metalorganic vapor-phase epitaxy and two steps of III-V material dry etching. For the DFB-PMC device, a high TE to TM polarization conversion efficiency (98.4%) over a wide range of DFB injection currents is reported at 1555 nm wavelength. For the DFB-PMC-DPS device, a nearly 60° rotation of the Stokes vector on the Poincaré sphere was obtained with a range of bias voltage from 0 to −3.0 V$-3.0\mathrm{V}$ at a laser drive current of 170 mA.

中文翻译：

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与侧壁光栅 DFB 激光器集成的无再生 AlGaInAs MQW 偏振控制器

偏振控制是高容量数据光通信系统的核心，例如偏振分复用器和斯托克斯矢量调制发射器。尽管被动偏振控制已经成熟，但单片集成偏振控制器和单纵模光源（例如分布式反馈 (DFB) 激光器）的实现具有重要意义。在这项研究中，我们报告了一种 AlGaInAs 多量子阱光子集成电路器件，它可以控制输出光源的偏振状态，由偏振模式转换器 (PMC)、差分移相器 (DPS) 和侧壁光栅分布反馈激光器。我们展示了一个非对称阶梯式高度脊波导 PMC 来实现 TE 到 TM 偏振转换和一个对称直波导 DPS 来实现从近似逆时针圆偏振到线性偏振的偏振旋转。基于相同的外延层方案，只需一步金属有机气相外延和两步 III-V 材料干法刻蚀，即可将所有 PMC、DPS 和 DFB 激光器单片集成。对于 DFB-PMC 器件，据报道在 1555 nm 波长处，在很宽的 DFB 注入电流范围内，TE 到 TM 偏振转换效率很高 (98.4%)。对于 DFB-PMC-DPS 器件，在 0 到 0 到 DFB激光器仅需一步金属有机气相外延和两步III-V族材料干法刻蚀即可实现单片集成。对于 DFB-PMC 器件，据报道在 1555 nm 波长处，在很宽的 DFB 注入电流范围内，TE 到 TM 偏振转换效率很高 (98.4%)。对于 DFB-PMC-DPS 器件，在 0 到 0 到 DFB激光器仅需一步金属有机气相外延和两步III-V族材料干法刻蚀即可实现单片集成。对于 DFB-PMC 器件，据报道在 1555 nm 波长处，在很宽的 DFB 注入电流范围内，TE 到 TM 偏振转换效率很高 (98.4%)。对于 DFB-PMC-DPS 器件，在 0 到 0 到− 3.0 V $-3.0\mathrm{V}$，激光驱动电流为 170 mA。