Hassanien Ahmed E, Ghoname Amr O, Chow Edmond, Goddard Lynford L, Gong Songbin
Opt Express. 2022 Jan 31;30(3):4543-4552. doi: 10.1364/OE.446665.
In this paper, we designed, implemented, and characterized compact Mach-Zehnder interferometer-based electro-optic modulators. The modulator utilizes spiral-shaped optical waveguides on Z-cut lithium niobate and the preeminent electro-optic effect which is applied using top and bottom electrodes. Optical waveguides are made of rib etched lithium niobate waveguides with bottom silicon oxide cladding, while SU8 polymer covers the top and sides of the rib waveguides. The proposed implementation resulted in low optical losses < 1.3 dB/cm. Moreover, we achieved compact modulators that fit 0.286 cm and 2 cm long optical waveguides in 110 µm × 110 µm and 300 µm × 300 µm areas, respectively. For single arm modulation, the modulators achieved a VπL of 7.4 V.cm and 6.4 V.cm and 3-dB bandwidths of 9.3 GHz and 2.05 GHz, respectively. Push-pull modulation is expected to cut these VπL in half. The proposed configuration avoids traveling wave modulation complexities and represents a key development towards miniature and highly integrated photonic circuits.
在本文中，我们设计、实现并表征了基于紧凑型马赫曾德尔干涉仪的电光调制器。该调制器利用Z切铌酸锂上的螺旋形光波导以及通过顶部和底部电极施加的卓越电光效应。光波导由带有底部氧化硅包层的肋蚀刻铌酸锂光波导制成，而SU8聚合物覆盖肋光波导的顶部和侧面。所提出的实施方案导致光损耗低至<1.3 dB/cm。此外，我们实现了紧凑型调制器，分别在110 µm×110 µm和300 µm×300 µm的区域内适配0.286 cm和2 cm长的光波导。对于单臂调制，调制器分别实现了7.4 V·cm和6.4 V·cm的VπL以及9.3 GHz和2.05 GHz的3 dB带宽。推挽调制预计会将这些VπL减半。所提出的配置避免了行波调制的复杂性，代表了朝着微型化和高度集成光子电路发展的关键一步。
