作者
Mark Lawrence, Ningning Xu, Xueqian Zhang, Longqing Cong, Jiaguang Han, Weili Zhang, Shuang Zhang
发表日期
2014/8/29
期刊
Physical review letters
卷号
113
期号
9
页码范围
093901
出版商
American Physical Society
简介
By utilizing the vector nature of light as well as the inherent anisotropy of artificial meta-atoms, we investigate parity time symmetry breaking in polarization space using a metasurface with anisotropic absorption, whose building blocks consist of two orthogonally orientated meta-atoms with the same resonant frequency but different loss coefficients. By varying their coupling strength, we directly observe a phase transition in the eigenpolarization states of the system, across which the long axis of the eigenpolarization ellipses experience a sudden rotation of 45°. Despite the lack of rotational symmetry of the metasurface, precisely at the phase transition, known as the exceptional point, the eigenmodes coalesce into a single circularly polarized state. The symmetric metasurfaces are experimentally implemented at terahertz frequencies.
学术搜索中的文章
M Lawrence, N Xu, X Zhang, L Cong, J Han, W Zhang… - Physical review letters, 2014