Zeng Y S, Qu S W, Wang C, Chen B J, Chan C
Opt Express. 2019 Apr 1;27(7):9941-9954. doi: 10.1364/OE.27.009941.
Vertical-emitting optical couplers that convert in-plane guided light to out-of-plane emission are crucial elements for future photonic integrated circuits. However, traditional vertical-coupling elements, such as grating couplers, by default radiate light in both upward and downward directions, leading to a significant reduction of device efficiency. In this paper, we propose to solve this problem using a novel nanopatch antenna array, inspired by patch antenna theories commonly deployed in microwave circuits. The proposed nanopatch array features an up-to-down emission directionality up to 12.91 dBc and a wide operating bandwidth of over 400 nm simultaneously. Compared with a typical waveguide grating antenna, our design shows a significantly higher free-space gain of 24.27 dBi. The unidirectional, efficient, and broadband antenna arrays presented here are promising for a range of integrated photonics applications, including inter-chip photonic interconnects, light ranging and detection, optical communications, and biological imaging.
将面内导光转换为面外发射的垂直发射光耦合器是未来光子集成电路的关键元件。然而，传统的垂直耦合元件，如光栅耦合器，默认情况下会在向上和向下两个方向辐射光，导致器件效率显著降低。在本文中，我们受微波电路中常用的贴片天线理论启发，提出使用新型纳米贴片天线阵列来解决这个问题。所提出的纳米贴片阵列同时具有高达12.91 dBc的上下发射方向性和超过400 nm的宽工作带宽。与典型的波导光栅天线相比，我们的设计显示出显著更高的24.27 dBi的自由空间增益。这里展示的单向、高效和宽带天线阵列在一系列集成光子学应用中具有前景，包括芯片间光子互连、光测距与检测、光通信和生物成像。
