The emerging fields of non-Hermitian optics and photonics are inspiring radically new, unconventional ways of mixing active and passive constituents to attain exotic light–matter interactions. Here, inspired by the concept of parity-time symmetry, we propose and explore a class of non-Hermitian multilayered metamaterials, featuring spatial modulation of gain and loss, which can exhibit extreme anisotropy in the epsilon-near-zero regime. Specifically, via analytic and numerical studies, we investigate the intriguing parameter tunability and wave-propagation effects that can occur in these media due to the delicate interplay between gain and loss. These include, for instance, field canalization, subdiffractive imaging, and reconfigurable waveguiding/radiation, and remarkably, they do not rely on the presence of metallic constituents. Moreover, we show that the extreme-parameter regime of interest is technologically feasible, e.g., in terms of material constituents based on dye-doped indium tin oxide at near-infrared wavelengths. Our outcomes bring about new, largely unexplored dimensionalities and possibilities in the tailoring of the effective properties of non-Hermitian metamaterials and open the door to a wealth of possible developments and applications in reconfigurable nanophotonics scenarios.

中文翻译：

---

极参数非赫米特电超材料

非赫米特光学和光子学的新兴领域正在激发全新的，非常规的方式来混合主动成分和被动成分，以实现奇异的光-质相互作用。在这里，受奇偶时间对称性概念的启发，我们提出并探索了一类非厄米特多层超材料，其特征是增益和损耗的空间调制，可以表现出极大的各向异性。在ε接近零的状态。具体来说，通过分析和数值研究，我们研究了由于增益和损耗之间的微妙相互作用而在这些介质中可能发生的有趣的参数可调性和波传播效果。这些包括，例如，场渠化，亚衍射成像和可重构的波导/辐射，并且值得注意的是，它们不依赖于金属成分的存在。此外，我们表明感兴趣的极端参数机制在技术上是可行的，例如，在近红外波长上基于染料掺杂的铟锡氧化物的材料成分方面。我们的成果带来了新的，