Starting from the fully vectorial coupled local-mode theory, a general design rule for adiabatic waveguide design is derived. The design rule guarantees adiabaticity and puts an upper limit on the transmission loss of any guided wave transformation. The rule is applicable to any waveguide geometry, admits multi-dimensional optimization, and accounts for radiative loss to guided and radiation modes. Moreover, the design technique is enhanced with further optimization procedures that eliminate coupling between particular pairs of modes. The utility of this toolbox of design rules and methods is illustrated through the design of a 2×2 coupler and a bilayer waveguide transition. These design procedures can be used to optimize single-mode and multimode photonic devices by varying one or more waveguide parameters.

中文翻译：

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绝热导波光学器件–通用设计和优化方法的工具箱

从全矢量耦合局部模式理论出发，推导了绝热波导设计的一般设计规则。设计规则保证了绝热性，并对任何导波变换的传输损耗设置了上限。该规则适用于任何波导几何形状，允许进行多维优化，并考虑到引导模式和辐射模式的辐射损耗。而且，通过进一步的优化程序来增强设计技术，这些优化程序消除了特定模式对之间的耦合。通过2×2耦合器和双层波导过渡的设计，说明了该设计规则和方法工具箱的实用性。通过改变一个或多个波导参数，这些设计程序可用于优化单模和多模光子器件。