Theoretical seminar | 21 December 2022

This seminar will introduce my research experience during my study in China, mainly including three parts, the first is structure-function integrated electromagnetic metasurfaces absorber. In order to expand the practical application of metamaterials, we designed a carbon fiber double-ring microwave absorbing metamaterial, and the honeycomb arrangement can effectively enhance the overall strength and corrosion resistance of the metamaterial. Second part is anomalous transmission and reflection based on Huygens’ metasurface, by changing the size of the layer of metal to adjust to the surface of the Huygens equivalent electromagnetic source, realize the independence of equivalent impedance and admittance regulation, and the structure design without a metal backboard. Last part is about modulation of Polarization eigenstates by Parity time (PT) symmetric metasurface. The non-Hermitian system has novel physical properties compared with the Hermitian system. Prosed a bilayer non-Hermitian metasurface. The transformation of the system's eigen polarization state from symmetric phase to broken phase is obtained by simulation, and the generation of exceptional point (EP) can be observed. Using the PT symmetric metasurface, two sensing schemes are designed to achieve high sensitivity of temperature and refractive index.

Main paper/arXiv, related to the seminar, and other references

1. R. Q. Zhao, Z. Zhu, G. H. Dong, T. T. Lv, Y. X. Li, C. Y. Guan, J. H. Shi, and H. Zhang, “High-efficiency Huygens' metasurface for terahertz wave manipulation,” Opt. Lett. 44, 3482 (2019).
2. M. Lawrence, N. Xu, X. Zhang, L. Cong, J. Han, W. Zhang, and S. Zhang, “Manifestation of PT Symmetry Breaking in Polarization Space with Terahertz Metasurfaces,” Phys. Rev. Lett. 113, 093901 (2014).