Open AccessAnisotropic reflection oscillation in periodic multilayer structures of parity-time symmetry
Author(s) -
Xuefeng Zhu,
YuGui Peng,
Degang Zhao
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.018401
Subject(s) - optics , parity (physics) , anisotropy , oscillation (cell signaling) , reflection (computer programming) , physics , scattering , symmetry (geometry) , condensed matter physics , geometry , quantum mechanics , mathematics , computer science , genetics , biology , programming language
We show that periodic multilayer structures with parity-time (PT) symmetries imposed by a balanced arrangement of gain and loss can exhibit anisotropic reflection oscillation patterns as the number of unit-cells is increasing. At the minima of reflection oscillation patterns, the PT symmetric medium exhibits bidirectional transparency with the eigenvalues of the scattering matrix degenerated, where the PT symmetric set-up can still render directional responses due to the one-way field localization inside the system. With certain number of unit-cells, the PT symmetric crystal is unidirectionally invisible. More complicated reflection/transmission oscillations can be observed by segregating neighboring unit-cells with a uniform dielectric layer. Our results may pave the way towards a new class of functional optical devices with intriguing and unexpected directional responses.