Madden S, Jin Z, Choi D, Debbarma S, Bulla D, Luther-Davies B
Centre for Ultrahigh Bandwidth Devices for Optical Systems, Laser Physics Centre, Australian National University, Canberra, Australia.
Opt Express. 2013 Feb 11;21(3):3582-94. doi: 10.1364/OE.21.003582.
Highly nonlinear planar glass waveguides have been shown to be useful for all optical signal processing. However, the typical SMF-28 fiber to waveguide coupling loss of ~5dB/end remains a barrier to practical implementation. Low loss coupling to a fiber using vertical tapering of the waveguide film is analyzed for rib and nanowire waveguides and experimentally demonstrated for ribs showing polarization and wavelength independence over >300nm bandwidth. Tapers with essentially zero excess loss led to total losses from the waveguide to fiber core of 1.1dB per facet comprising only material absorption (0.75dB) and mode overlap loss (0.36dB), both of which can be eliminated with improvements to processing and materials.
高度非线性平面玻璃波导已被证明可用于全光信号处理。然而，典型的单模光纤28（SMF - 28）与波导的耦合损耗约为5dB/端，这仍然是实际应用的一个障碍。针对肋形波导和纳米线波导，分析了利用波导薄膜垂直渐变实现与光纤的低损耗耦合，并通过实验证明了肋形波导在大于300nm带宽上具有偏振和波长独立性。具有基本为零的额外损耗的渐变导致从波导到光纤纤芯的每面总损耗为1.1dB，仅包括材料吸收（0.75dB）和模式重叠损耗（0.36dB），通过改进工艺和材料，这两种损耗都可以消除。
