In this work, we take fractional stimulated Raman adiabatic passage (f-STIRAP) for the design of functional acoustic waveguide (WG) coupler into account. Assisted by the agreement in the form between Schrödinger equation in quantum mechanics and the coupled-mode equation of classical waves, the quantum three-level system is mapped onto the acoustic three-WG system with space-varying coupling actions between composing WGs. The output port of the coupler can be selected by adopting different superposition forms of incident waves, which is utilized to build a one-way acoustic mode converter based on double f-STIRAP. By further constructing a functional acoustic metamaterial arrayed by mode converters, a desired beam splitting behavior can be generated unidirectionally in a broadband. Our work bridges f-STIRAP and the design of acoustic metamaterial, which may have profound impacts on exploring quantum technologies for promoting advanced acoustic functional devices with simple configuration and excellent performance.

中文翻译：

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受双分数受激拉曼绝热通道控制的声学超材料中的单向光束分裂

在这项工作中，我们将分数受激拉曼绝热通道 ​​(f-STIRAP) 用于设计功能性声波导 (WG) 耦合器。借助量子力学中的薛定谔方程与经典波的耦合模式方程在形式上的一致，将量子三能级系统映射到声学三工作组系统上，组成工作组之间具有空间变化的耦合作用。通过采用不同的入射波叠加形式，可以选择耦合器的输出端口，用于构建基于双f-STIRAP的单向声学模式转换器。通过进一步构建由模式转换器排列的功能性声学超材料，可以在宽带中单向产生所需的分束行为。我们的工作将 f-STIRAP 与声学超材料的设计联系起来，