Here, a two‐dimensional (2D) hole‐type square lattice photonic crystal is shown to achieve invisibility cloaking based on all‐angle self‐collimation. The proposed structure, which is composed of the high‐refraction‐index dielectric material PbTe (n_PbTe ≈ 6), is applicable in the mid‐infrared (mid‐IR) frequency range. The cloaking region is capable of hiding any object of any shape and size since the incoming wave does not interact with the cloaked object. The optimization process and the functionality of the proposed structure are investigated by equal frequency contour analysis and the finite difference time domain (FDTD) method.

中文翻译：

---

二维方格光子晶体中基于全角度自准直的隐形隐身

此处显示了二维（2D）孔型方晶格光子晶体，该晶体可基于全角度自准直实现隐形隐身。所提出的结构由高折射率介电材料PbTe（n _PbTe≈6  ）组成，适用于中红外（mid-IR）频率范围。由于入射波不与隐蔽物体相互作用，因此隐蔽区域能够隐藏任何形状和大小的任何物体。通过等频轮廓分析和时域有限差分（FDTD）方法研究了所提出结构的优化过程和功能。