A conformal transformation approach to wide-angle illusion device and absorber

• Main Authors: Huang, Yao, Zhang, Youming, Zhang, Jingjing, Liu, Dongjue, Wang, Qijie, Zhang, Baile, Luo, Yu
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2023
• Subjects: Science::Physics; Engineering::Electrical and electronic engineering; Illusion Optics; Metamaterial Absorber
• Online Access: https://hdl.handle.net/10356/164875
• Institution: Nanyang Technological University

We theoretically investigate the illusion device designed by a conformal transformation that can render an elliptic defect behave like a flat mirror. Different from illusion devices consisting of the complementary medium and anti-object with negative permittivity and permeability, our proposed illusion device requires only isotropic positive permittivity medium. It offers a possible route to eliminate the lateral shift in the conventional quasi-conformal carpet cloak. Interestingly, with the same conformal transformation, we can achieve an impedance-matched flat absorber by simply varying the shape and the refractive index of the defects. Both the illumination device and the absorber in our design have broad bandwidth, wide-illumination range and polarization-insensitive performance.