Wang Zelu, Liu Yingjie, Wang Zi, Liu Yilin, Du Jiangbing, Song Qinghai, Xu Ke
Opt Lett. 2021 Sep 1;46(17):4232-4235. doi: 10.1364/OL.430827.
Extending the optical communication wavelengths to 2 µm can significantly increase data capacity. Silicon photonics, which is a proven device integration technology, has made rapid progress at 2 µm recently. As a fundamental functional element in the photonic design kit, the 3 dB power splitter has been extensively studied in both the 1.55 µm and 2 µm regime. While the device is highly desirable to operate over both wave bands, the large waveguide dispersion in silicon makes it challenging. In this work, we demonstrate an ultra-broadband power splitter on silicon, which has a 0.2 dB bandwidth exceeding 520 nm from 1500 to 2020 nm according to simulations. The beam splitter is realized by a triple tapered Y-junction, and its operational bandwidth is greatly increased by subwavelength grating structure. The device has an ultra-compact footprint of only 3µ×2µ. Due to the limitations on the setup and coupling technique, we measure the device bandwidth in 1.55 µm and 2 µm wave bands. The device insertion loss is measured to be below 0.4 dB from 1500 to 1620 nm and from 1960 to 2020 nm, respectively. According to these results, the proposed device is believed to be capable of operating over a broadband from 1.55 µm and 2 µm wavelengths.
将光通信波长扩展到2微米可显著提高数据容量。硅光子学作为一种成熟的器件集成技术，最近在2微米波长处取得了快速进展。作为光子设计套件中的基本功能元件，3分贝功率分配器在1.55微米和2微米波段都得到了广泛研究。虽然该器件非常希望能在两个波段上工作，但硅中的大波导色散使其具有挑战性。在这项工作中，我们展示了一种硅基超宽带功率分配器，根据模拟，其0.2分贝带宽在1500至2020纳米范围内超过520纳米。该分束器由一个三重锥形Y形结实现，其工作带宽通过亚波长光栅结构大大增加。该器件具有仅3µ×2µ的超紧凑尺寸。由于设置和耦合技术的限制，我们在1.55微米和2微米波段测量了该器件的带宽。测得该器件在1500至1620纳米以及1960至2020纳米处的插入损耗分别低于0.4分贝。根据这些结果，该器件被认为能够在1.55微米和2微米波长的宽带范围内工作。
