Parity-time symmetry transition and exceptional points in terahertz metal–graphene hybrid metasurface with switchable transmission and reflection characteristics
Zhenkai Li, Weikui Yang, Kun Wang, Chunyang Jiang, Xiaotong Sang, Jian Wang, Xinyu Lv, Huiyun Zhang, Yuping Zhang
Abstract
. The tunable asymmetric loss and PT symmetry transition can be actively controlled by changing the Fermi energy of the graphene strip. Interestingly, owing to the special chirality of the structure, the original metasurface, and the mirrored metasurface degenerate into a circularly polarized state with opposite rotations at the same Fermi energy. The π-phase mutation at EP is observed following the interaction of circularly polarized waves and the metasurface and is expected to have good application prospects in environmental monitoring and gas sensing.
Topics & Concepts
Terahertz radiationDegenerate energy levelsGrapheneReflection symmetryCondensed matter physicsPhysicsPolarization (electrochemistry)Parity (physics)Circular polarizationReflection (computer programming)Hamiltonian (control theory)Mirror symmetryPhase transitionChirality (physics)Fermi levelOpticsSymmetry breakingQuantum mechanicsChemistrySpontaneous symmetry breakingMicrostripNambu–Jona-Lasinio modelComputer scienceMathematicsMathematical optimizationProgramming languagePhysical chemistryGeometryElectronQuantum Mechanics and Non-Hermitian PhysicsMetamaterials and Metasurfaces ApplicationsTopological Materials and Phenomena