Since the initial discovery of Dyakonov surface waves at a flat infinite interface of two dielectrics, at least one of which is positively anisotropic, extensive research has been conducted towards their theoretical and experimental studies in materials with positive anisotropy. The potential applications of these waves were initially limited due to the stringent conditions for their existence and the requirement for position anisotropy. In our study, we present the theoretical prediction and experimental observation of a novel type of Dyakonov surface waves that propagate along the flat strip of the interface between two dielectrics with negative anisotropy. We demonstrate that the conditions for surface waves are satisfied for negatively anisotropic dielectrics owing to the specific boundaries of the strip waveguide confined between two metallic plates. We study such modes theoretically by using the perturbation theory in the approximation of weak anisotropy and demonstrate that the electromagnetic field distribution in these modes is chiral. Experimental verification of theoretical predictions is made in the microwave range using 3D-printed negatively anisotropic water-dielectric metamaterial slabs. The existence of Dyakonov surface waves in negative crystals prompts a reassessment of the list of materials suitable for practical realization of these waves in the visible and infrared ranges. Due to the ability of the considered modes to transmit chiral light, they have potential in the sensing of chiral organic molecules.

中文翻译：

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负各向异性介电晶体中的迪亚科诺夫表面波

自从最初在两个电介质的平坦无限界面上发现迪亚科诺夫表面波以来，至少其中一个是正各向异性，他们对正各向异性材料的理论和实验研究进行了广泛的研究。由于其存在的严格条件和位置各向异性的要求，这些波的潜在应用最初受到限制。在我们的研究中，我们提出了一种新型迪亚科诺夫表面波的理论预测和实验观察，该表面波沿着两个电介质之间界面的平坦条带传播负各向异性。我们证明，由于条形波导的特定边界限制在两个金属板之间，负各向异性电介质满足表面波的条件。我们利用弱各向异性近似中的微扰理论从理论上研究了这些模式，并证明了这些模式中的电磁场分布是手性的。使用 3D 打印的负各向异性水介电超材料板在微波范围内对理论预测进行了实验验证。负晶体中迪亚科诺夫表面波的存在促使人们重新评估适合在可见光和红外范围内实际实现这些波的材料清单。由于所考虑的模式具有传输手性光的能力，它们在手性有机分子的传感方面具有潜力。