激光与光电子学进展, 2016, 53 (6): 060603, 网络出版: 2016-06-06
双边调制布拉格波导光栅的特性研究
Characteristics of the Double-Side Modulation Waveguide Bragg Grating
光通信 布拉格波导光栅 双边调制 转移矩阵理论 反射谱 optical communications Bragg waveguide gratings double-side modulation transfer matrix theory reflection spectrum properties
摘要
设计了一种一次性制备双边调制布拉格波导光栅的新方法。通过周期性改变波导的宽度实现波导光栅的空间调制,其优势是利用波导的制备工艺将波导及光栅一次性制备,工艺简单。基于转移矩阵理论,研究了该结构的波导光栅反射谱特性与波导宽度、波导宽度差、光栅占空比及波导宽度变化的形状的关系。结果表明,双边调制比皱阶调制3 dB带宽明显变大,最大反射率稍有增大。当波导宽度差不变时,随波导宽度增大,最大反射率和零值带宽都随之减小。当波导宽度不变时,随波导宽度差增大,最大反射率和零值带宽都随之增大。当波导宽度与波导宽度差均不变时,光栅占空比为1/2时最大反射率最高,零值带宽最大。且波导宽度差足够大时,可通过改变占空比来改变零值带宽。波导变化的形状对波导光栅的反射谱性能影响较小。
Abstract
A new preparation method of the double-side modulation Bragg waveguide grating by one step is proposed. In the structure, spatial modulation of the waveguide grating is achieved by periodically changing the width of the waveguide. The advantage of this structure is that waveguide and grating are achieved at the same time by using a simple waveguide fabrication technology. According to transfer matrix theory, the relationship between the reflection spectrum characteristics of this structure and the waveguide width, the difference of waveguide width, the duty cycle of gratings, the changes of the waveguide in the shape is studied. Results show that 3 dB bandwidth of grating with double-side modulation is wider than that of grating with corrugated modulation. At the same time, the maximum reflectivity is increased slightly. When the difference of waveguide width is fixed, the maximum reflectivity and bandwidth decrease while the waveguide width increases. In addition, when the waveguide width is fixed, the maximum reflectivity and bandwidth increase while the waveguide width increases. When both the waveguide width and its difference are both fixed, the maximum reflectivity and bandwidth achieve these maximums at the duty cycle of 1/2. Furthermore, the bandwidth can be controlled by changing the duty cycle when the difference of waveguide width is large enough. And the waveguide shape change has a small impact on the reflection spectrum properties of waveguide grating.
张爱玲, 孙钦芳*, 闫广拓. 双边调制布拉格波导光栅的特性研究[J]. 激光与光电子学进展, 2016, 53(6): 060603. Zhang Ailing, Sun Qinfang, Yan Guangtuo. Characteristics of the Double-Side Modulation Waveguide Bragg Grating[J]. Laser & Optoelectronics Progress, 2016, 53(6): 060603.