Waves typically propagate very differently through a homogeneous medium like free space than through an inhomogeneous medium like a complex dielectric structure. Here we present the surprising result that wave solutions in two-dimensional free space can be mapped to a solution inside a suitably designed non-Hermitian potential landscape such that both solutions share the same spatial distribution of their wave intensity. The mapping we introduce here is broadly applicable as a design protocol for a special class of non-Hermitian media across which specific incoming waves form scattering-free propagation channels. This protocol naturally enables the design of structures with a broadband unidirectional invisibility for which outgoing waves are indistinguishable from those of free space. We illustrate this concept through the example of a beam that maintains its Gaussian shape while passing through a randomly assembled distribution of scatterers with gain and loss.

中文翻译：

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跨非赫米特媒体的无散射隐形渠道

通常，波在均匀介质（如自由空间）中的传播与通过非均匀介质（如复杂介电结构）的传播非常不同。在这里，我们提出了令人惊讶的结果，即二维自由空间中的波解可以映射到适当设计的非Hermitian势景观内部的解，从而使两个解共享其波强度的相同空间分布。我们在此处介绍的映射可广泛用作特殊类非Hermitian媒体的设计协议，特定的传入波在该类非特定媒体上形成无散射传播通道。该协议自然可以设计出具有宽带单向不可见性的结构，对于这些结构，出射波与自由空间的出射波无法区分。