Tyndall Nathan F, Stievater Todd H, Kozak Dmitry A, Pruessner Marcel W, Rabinovich William S
Opt Express. 2020 Nov 9;28(23):34927-34934. doi: 10.1364/OE.405864.
To perform waveguide-enhanced Raman spectroscopy (WERS) or fluorescence spectroscopy in a compact device, the optical fibers to couple the passive photonic circuit to the laser source and detector require attachment directly to the die. This necessitates the integration of edge couplers and waveguide-based filters to isolate the fiber background emission from the on-chip signal, while efficiently coupling the pump laser and detector to the input and output fibers, respectively. In this work, we experimentally demonstrate the successful integration of four-port lattice filters with sensing spirals and inverse-taper edge couplers in a passive photonic circuit. We further show that the four-port lattice filter enables the collection of backscattered on-chip Stokes signal, improving and simplifying overall system performance.
为了在紧凑的设备中进行波导增强拉曼光谱（WERS）或荧光光谱分析，将无源光子电路与激光源和探测器耦合的光纤需要直接附着到芯片上。这就需要集成边缘耦合器和基于波导的滤波器，以将光纤背景发射与芯片上的信号隔离开来，同时分别将泵浦激光和探测器有效地耦合到输入和输出光纤上。在这项工作中，我们通过实验证明了在无源光子电路中成功集成了具有传感螺旋和反锥形边缘耦合器的四端口晶格滤波器。我们进一步表明，四端口晶格滤波器能够收集芯片上的背向散射斯托克斯信号，从而改善并简化了整体系统性能。
