Shen Yun, Deng Xiao Hua, Chen Lin
Opt Express. 2014 Aug 11;22(16):19440-7. doi: 10.1364/OE.22.019440.
Recently, unidirectional invisibility has been demonstrated in parity-time (PT) symmetric periodic structures and has attracted great attention. Nevertheless, fabrication of a complex periodic structure may not be practically easy. In this paper, a simple two-layer non-PT-symmetric slab structure is proposed to realize unidirectional invisibility. We numerically show that in such conventional structure consisting of two slabs with different real parts of refractive indices, unidirectional invisibility can be achieved as proper imaginary parts of refractive indices and thicknesses of the slabs are satisfied. Moreover, the unidirectional invisibility can be converted to unidirectional reflection when the imaginary parts of the refractive indices are tuned to their odd symmetric forms.
最近，在奇偶时间（PT）对称周期结构中已经证明了单向隐身性，并引起了广泛关注。然而，制造复杂的周期结构在实际中可能并不容易。本文提出了一种简单的双层非PT对称平板结构来实现单向隐身性。我们通过数值计算表明，在这种由具有不同实部折射率的两个平板组成的传统结构中，当平板的折射率虚部和厚度满足一定条件时，可以实现单向隐身性。此外，当折射率的虚部调整为其奇对称形式时，单向隐身性可以转换为单向反射。
