微纳光纤耦合器光致热引起的全光强度调控特性

All-Optical Intensity Modulation Characteristics of Optical Microfiber Coupler Based on Light Induced Thermal Effect

对微纳光纤耦合器(OMC)光吸收致热引起的全光强度调控特性进行了理论分析和实验研究。理论分析结果显示,OMC全光强度调控器件的调制响应效率与OMC腰区长度、抽运光在OMC腰区的损耗系数及抽运调制光强成正比,而与OMC腰区耦合光纤的半径成反比。通过实验将强度调制的980nm抽运光注入OMC以加热其腰区,实现了对OMC传输的1550nm工作光的全光调控功能。在百微瓦量级的调控光功率作用下,OMC全光强度调控器件即可实现整周期、大调制深度的强度调制,且在较小调制光功率下,调制响应信号幅度与调制信号幅度呈线性响应关系。OMC光热调控最小响应调制光功率为几十微瓦量级。研究成果为开发基于OMC光致热效应的光衰减、光开关及强度调制器等全光功能器件提供了实验数据,并为微纳光子集成光路热稳定性管控及片基量子通信系统安全性研究提供了可借鉴的研究方案。

Based on light induced thermal effect,all-optical intensity modulation characteristics of optical microfiber coupler（OMC）are studied.The theoretical analysis shows that,the modulation response efficiency of OMC is proportional to the waist length,loss coefficient,and pump modulation intensity,and is inversely proportional to the radius of the OMC waist coupling fiber.In the experiment research,the intensity modulated 980 nm pump light is injected into the OMC to heat the waist region,and the all-optical control function of the 1550 nm working light transmitted by OMC is obtained.The results show that,the OMC can realize intensity modulation with a whole cycle and a large modulation depth under modulation pump power of hundreds of microwatts.In addition,the amplitude of the modulation response signal has a linear response to the amplitude of intensity modulated 980 nm pump light in a low power region.The threshold of the required modulated pump light power is as low as several dozens of micro watts.The research has provide experimental data for the development of all-optical functional devices,such as optical attenuation,optical switch,intensity modulator,and it also provides a reference scheme for the control of the thermal stability of photonics integrated equipment and the security of quantum communication system.