论文标题
低损坏，高带宽纤维到芯片耦合，使用上限绝热锥形纤维
Low-loss, high-bandwidth fiber-to-chip coupling using capped adiabatic tapered fibers
论文作者
论文摘要
我们演示了绝热的锥形纤维，这些纤维终止于亚微米尖端，这些纤维尖端具有较高的指数材料，可与片上的波导偶联。这种覆层可以使耦合到高索引波导，而不会使氧化物被埋葬。引入了一种用高索引聚合物覆盖锥形纤维尖端的技术。研究了常规的锥形波导和分叉的锥形波导结构，用于从包裹纤维到片上波导的耦合。我们发现分叉的波导有助于对齐和包装，而传统的锥度则导致更高的带宽。从纤维通过叉子耦合器到亚微米硅氮化硅波导的插入损失为1.1 dB，3 dB频带宽度为90 nm。包装设备中的耦合损耗为1.3 dB。纤维耦合到常规的锥形波导，损耗为1.4 dB，3 dB带宽延伸，超出了测量设备的范围，估计超过250 nm。
We demonstrate adiabatically tapered fibers terminating in sub-micron tips that are clad with a higher-index material for coupling to an on-chip waveguide. This cladding enables coupling to a high-index waveguide without losing light to the buried oxide. A technique to clad the tip of the tapered fiber with a higher-index polymer is introduced. Conventional tapered waveguides and forked tapered waveguide structures are investigated for coupling from the clad fiber to the on-chip waveguide. We find the forked waveguide facilitates alignment and packaging, while the conventional taper leads to higher bandwidth. The insertion loss from a fiber through a forked coupler to a sub-micron silicon nitride waveguide is 1.1 dB and the 3 dB-bandwidth is 90 nm. The coupling loss in the packaged device is 1.3 dB. With a fiber coupled to a conventional tapered waveguide, the loss is 1.4 dB with a 3 dB bandwidth extending beyond the range of the measurement apparatus, estimated to exceed 250 nm.
