中红外硅基调制器研究进展（特邀）

硅材料在1.1~8.5 μm有非常低的吸收损耗，因此硅基光电子学有望扩展到中红外波段。并且随着通信窗口扩展、气体分子检测、红外成像等应用需求的出现，硅基中红外波段器件研发工作的开展势在必行。在中红外波段硅基光电子器件中，硅基调制器有着举足轻重的地位:它是长波光通信链路中不可或缺的一环，还可以应用在片上传感系统中提高信噪比、实现光开关等功能。研究发现，相比于近红外波段，硅和锗材料在中红外波段有更强的自由载流子效应和热光效应，因此，基于硅基材料的中红外调制器具有独天得厚的优势。系统总结了中红外硅基调制器的发展趋势和研究现状，介绍了基于硅和锗材料的电光调制器以及热光调制器的工作原理和最新研究进展，最后对中红外硅基调制器进行了总结与展望。

Research progress of mid-infrared silicon-based modulators (Invited)

Silicon-based photonics is expected to be extended to the mid-infrared (MIR) wavelength, due to the low absorption of silicon (Si) material in the range of 1.1 μm to 8.5 μm. With the needs emergence of communication window expansion, gas molecular detection, infrared imaging and other applications, the development of silicon-based devices in the mid-infrared wavelength is imperative. Silicon-based modulator plays an important role in the research and development of silicon-based optoelectronic devices in MIR. It is an indispensable link in long wave optical communication system, and can be used in on-chip sensing system to improve the signal-to-noise ratio and realize optical switching. It is found that silicon and germanium materials have greater free carrier effect and thermal-optical effect in the MIR band than that in the near-infrared band (NIR). It is proved that silicon-based materials have unique advantages in the development of mid-infrared modulators. The development trend and research status of MIR silicon-based modulators were summarized. The working principle and latest research progress of electro-optic modulators and thermal-optic modulators based on silicon and germanium materials were introduced. Finally, the mid-infrared silicon-based modulators were summarized and prospected.