Unidirectional radiation is of particular interest in high‐power lasing and optics. Commonly, however, it is difficult to achieve a unidirectional profile in such a system without breaking reciprocity. Recently, assisted by metamaterials without structural symmetry, antennas that radiate asymmetrically have been developed, hence providing the possibility of achieving unidirectionality. Nevertheless, it has been challenging to achieve extremely high radiation asymmetry in such antennas. Here, it is demonstrated that this radiation asymmetry is further enhanced when magnetic plasmons are present in the metamaterials. Experimentally, it is shown that a thin metamaterial with a thickness of ≈λ₀/8 can exhibit a forward‐to‐backward emission asymmetry of up to 1:32 without any optimization. The work paves the way for manipulating asymmetric radiation by means of metamaterials and may have a variety of promising applications, such as directional optical and quantum emitters, lasers, and absorbers.

中文翻译：

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超薄双各向异性超材料的巨大不对称辐射。

单向辐射在高功率激光和光学器件中特别重要。但是，通常，在不破坏可逆性的情况下，很难在这样的系统中实现单向分布。近来，在没有结构对称性的超材料的辅助下，已经开发了不对称辐射的天线，因此提供了实现单向性的可能性。然而，在这样的天线中实现极高的辐射不对称是具有挑战性的。在此证明，当超材料中存在磁等离子体时，这种辐射不对称性进一步增强。实验中，示出的是一个薄的超材料的厚度≈λ的₀/ 8在没有任何优化的情况下可显示高达1:32的前后发射不对称性。这项工作为通过超材料操纵不对称辐射铺平了道路，并且可能具有各种有前途的应用，例如定向光学和量子发射器，激光器和吸收器。