论文标题
一维平价对称光子晶体的带隙和奇异散射的单向弱可见性
Unidirectional weak visibility in band gap and singular scattering in conduction band of one-dimensional parity-time symmetric photonic crystal
论文作者
论文摘要
我们探讨了一维平价时间（$ \ Mathcal {pt} $） - 对称光子晶体的吸收和散射特性。除了熟悉的透射率和反射率外，我们还给出了广义吸收性的定义，以包括介电常数的介电作用的放大效果，此外，我们介绍了n个光电晶体的两侧的透射率，反射和吸收的数学表达，并以n的元素为元素的元素，以n的传递元素的元素来源。研究了该光子晶体的复杂带结构，并披露了$ \ Mathcal {pt} $ - 精确阶段和$ \ Mathcal {pt} $ - 损坏的相位的相应演变。在特殊点附近，我们发现了一些奇异的行为，双方的透射率和反射率都大于一个，甚至所有人同时达到了较大的值，因此，来自双方的相应吸收率为负。在频带间隙中，透射率为零，反射率一侧可能非常大，而来自另一侧的反射率很小，我们称这种现象为单向弱可见性。我们认为这些现象对光学设备的设计非常有益。
We explore the absorption and scattering properties of one dimensional parity-time ($\mathcal{PT}$)-symmetric photonic crystal. In addition to the familiar transmittance and reflectance, we give the definition of the generalized absorptance to include the amplifying effect of the dielectric with negative imaginary part of the permittivity, moreover, we present the mathematical expressions of the transmittance, reflectances and absorptances from both sides of this photonic crystal with N periods in terms of the elements of the transfer matrix of the primitive cell. The complex band structure of this photonic crystal is studied and the corresponding evolutions of the exceptional points, $\mathcal{PT}$-exact phase and $\mathcal{PT}$-broken phase are disclosed. Near the exceptional points, we find some singular behaviors, the transmittance and reflectances from both sides are all greater than one and even all reach large values at the same time, then the corresponding absorptances from both sides are negative. In the band gap, the transmittance is zero, the reflectance form one side can be very large, while the reflectance from the other side is very small, we call this phenomenon unidirectional weak visibility. We believe that these phenomena are very beneficial for the design of the optical devices.
