中心博士生王静的工作——Loss compensation of ultra-wideband electro-optic modulator in heterogeneous silicon/erbium-doped lithium niobate（增益补偿型超宽带硅/掺铒铌酸锂异质电光调制器）的相关成果近期被Optics Letters期刊接收发表，该工作得到了国家重点研发计划（2019YFB2203700）、国家自然科学基金（T2225023）的部分资助。电光调制器是集成光子芯片实现电光转换的核心器件，然而器件插入损耗限制了电光调制器集成能力的可拓展性。因此，我们首次在硅/掺铒铌酸锂异质平台上提出了一种新型的电光调制器。在本设计中，电光调制器的移相臂由硅和掺铒铌酸锂混合波导构成，可以同时实现电光调制和光放大。发挥了铌酸锂优异的电光特性，实现了超宽带调制；同时利用铒离子在掺铒铌酸锂中的受激跃迁进行光学放大，实现了有效的器件光学损耗补偿，避免先调制后放大时偏置漂移对器件性能造成的影响。理论分析表明，该电光调制器成功地实现了超过170 GHz的带宽，半波电压为3 V，此外，在1531 nm波长处，可实现 4 dB的有效传播补偿。在工艺方面，该电光调制器无需刻蚀铌酸锂，与传统的CMOS工艺兼容，可实现晶圆级集成。
摘要: Electro-optic modulators (EOMs) are indispensable elements for integrated photonic circuits. However, optical insertion losses limit the EOM capability towards scalable integration. Here, we propose a novel EOM schematic on a heterogeneous platform of silicon and erbium-doped lithium niobate (Si/Er:LN). In this design, the electro-optic modulation and optical amplification are simultaneously employed in phase shifters of the EOM. The excellent electro-optic property of lithium niobate is maintained to achieve an ultra-wideband modulation. Meanwhile, the optical amplification is performed by adopting the stimulated transitions of erbium ions in the Er:LN, leading to an effective optical loss compensation. Theoretical analysis shows that a bandwidth exceeding 170 GHz with a halfwave voltage of 3 V is successfully realized. Moreover, the efficient propagation compensation of ~4 dB is predicted at the wavelength of 1531 nm.