论文部分内容阅读
设计了一种基于二维光子晶体波导旁侧Fano微腔的全光二极管结构,实现光的单向传输。其关键技术是在光子晶体波导中采用简单反射层打破Fano微腔结构上的空间对称性,使得反射层两侧波导与微腔耦合效率不对称。两侧波导入射光激发微腔非线性克尔材料所需的光强阈值不同,从而实现单向导通功能。通过有限时域差分(FDTD)方法对其传输特性和性能进行了数值仿真和分析,研究发现:该结构在较低的光强阈值下可以实现正向导通、反向截止的全光二极管效果;该结构具有超快的响应时间,达到皮秒量级;该结构具有较高的最大透射率(达到90%)和较高的正反透射比。基于光子晶体结构的设计使得该器件可以具有很好的工作波长可调特性,并易于在目前半导体工艺基础上进行制作以及与其他器件集成。
A all-optical diode structure based on Fano microcavity on the side of two-dimensional photonic crystal waveguide is designed to realize the one-way transmission of light. The key technology is to use a simple reflective layer in the photonic crystal waveguide to break the spatial symmetry of the Fano microcavity structure so that the coupling efficiency between the waveguide and the microcavity on both sides of the reflective layer is not symmetrical. Both sides of the waveguide incident light excitation microcavity nonlinear Kerr material required light intensity threshold value in order to achieve unidirectional conduction. The finite-difference time-domain (FDTD) method is used to simulate and analyze the transmission characteristics and performance. The results show that the structure can realize the all-photodiode effect of forward turn-on and reverse turn-off at a lower light intensity threshold. The structure has an ultrafast response time up to picosecond order; the structure has a higher maximum transmittance (up to 90%) and a higher forward and reverse transmittance. The design based on the photonic crystal structure makes this device have good working wavelength tunable characteristic, and is easy to make on the basis of current semiconductor craft and integrate with other devices.