SGER: Modal Control in Hybrid Si/III-V Optoelectronic Circuits

光通信技术的下一个重大进展将涉及混合Si/III-V结构，其中III-V半导体的光产生和检测能力将与VLSI Si电子学结合起来。在这个方向上的一个重要步骤是一项被描述为“电泵浦混合AlGaInAs-硅倏逝激光器”的工作。“我们的提案沿着这个方向迈出了下一个重要的一步，我们提出了另一种混合Si/III-V光电电路的方法，它以最小的妥协结合了两种材料的优点。这是基于控制复合波导系统中的模式行为的能力。这种耦合波导系统的本征模（“超模”）可以被设计成使得光能被限制在Si或III-V波导中。这可以通过控制波导沿着传播方向的几何形状来实现，例如，通过定制Si波导宽度。数值计算预测，与现有的Si倏逝波激光器相比，这种设计的模式增益提高了四倍。一旦实验证明，“超模耦合”方案将导致更有效的设备，从而大大增加集成组件的密度。通过各种形式的宣传，将与广大科技界分享成果和发现。该项目的另一个目标是教育和培训一批学生从事科学研究，并指导他们了解科学发现的文化。

Objective The next major advance in optical communication technology will involve hybrid Si/III-V structures in which the light generation and detection capabilities of III-V semiconductor will join forces with VLSI Si electronics. An important step in this direction is a work described as "electrically pumped hybrid AlGaInAs-silicon evanescent lasers." Our proposal takes the next major step along this direction, we propose another approach to hybrid Si/III-V optoelectronic circuits which combines, with minimal compromise, the advantages of both materials. This is based on the ability to control the mode behavior in the composite waveguide system. Intellectual Merit The eigenmodes ("Supermodes") of such a coupled waveguide system can be designed such that the optical energy is confined to either the Si or the III-V waveguide. This can be achieved by controlling the geometry of the waveguides along the propagation direction, e.g., by tailoring the Si waveguide width. Numerical calculations predicted a four-fold enhancement of the modal gain with this design compared with that of the existing Si evanescent lasers. Broader Impacts Once experimentally demonstrated, the "supermode coupling" scheme will result in more efficient devices so as to greatly increase the density of integrated components. Through various kinds of exposure, the results and discoveries will be shared with the scientific and technological communities at large. Another goal of this project is to educate and train a group of students to pursue scientific research and to mentor them about the culture of scientific discovery.