Intermodal four-wave mixing (FWM) processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same waveguide. This allows, in principle, to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal processes. However, the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different modes. We demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM, which integrates mode conversion, multiplexing and de-multiplexing functionalities on-chip. The system enables wavelength conversion between pump waves and a signal located in different telecommunication bands (separated by 60 nm) with a 3 dB bandwidth exceeding 70 nm, which represents, to our knowledge, the widest bandwidth ever achieved in an intermodal FWM-based system.

中文翻译：

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基于布拉格散射模间四波混频的全集成宽带富硅氮化硅波长转换器

模间四波混频 (FWM) 过程最近引起了全光信号处理应用的极大兴趣，因为它可以控制激发同一波导不同空间模式的波的传播特性。原则上，与模内处理相比，这允许将信号放置在不同的光谱区域中并在相当大的带宽上满足相位匹配条件。然而，迄今为止报道的演示显示带宽有限，并且缺乏专为不同模式的宽带操作而设计的片上组件。我们在此展示了一种基于布拉格散射联模 FWM 的富硅氮化硅波长转换器，该转换器在片上集成了模式转换、复用和解复用功能。该系统能够在泵浦波和位于不同电信频段（间隔 60 nm）的信号之间进行波长转换，3 dB 带宽超过 70 nm，据我们所知，这代表了基于联运 FWM 的系统中迄今为止实现的最宽带宽。