Here we theoretically show, by designing and manipulating spatially inhomogeneous, non-uniform conductivity patterns across a single flake of graphene, that this single-atom-layered material can serve as a "one-atom-thick" platform for infrared metamaterials and transformation optical devices. It is known that by varying the chemical potential using gate electric and/or magnetic fields, the graphene conductivity in the THz and IR frequencies can be changed. This versatility provides the possibility that different "patches" on a single flake of graphene possess different conductivities, suggesting a mechanism to construct "single-atom-thick" IR metamaterials and transformation optical structures. Our computer simulation results pave the way for envisioning numerous IR photonic functions and metamaterial concepts-all on a "one-atom-thick" platform-of such we list a few here: edge waveguides, bent ribbon-like paths guiding light, photonic splitters and combiners, "one-atom-thick" IR scattering elements as building blocks for "flatland" metamaterials, thin strips as flatland superlenses, and "one-atom-thick" subwavelength IR lenses as tools for Fourier and transformation optics.
Quantum optical effective-medium theory for layered metamaterials
超材料的量子光学始于一个问题，即有效介质理论是否适用于经典光学。总的来说，答案是否定的。对于主动等离子体，但也为一些被动的超材料，我们表明，一个额外的有效介质参数是必不可少的，除了有效的指数，即有效的噪声光子分布。只有有了这个额外的参数，人们才能预测超材料中光的量子态保持得有多好。在超材料的量子光学中，单独的有效折射率并不总是足够的，而一个附加的有效参数就足够了，这一事实既具有基础性又具有实际意义。本文从具有线性增益和损耗的介质的量子电动力学的拉格朗日描述出发，计算了量子光在层状超材料中沿任意方向传播的有效噪声-光子分布，从而详细和推广了我们最近的工作[ E. Amooghorban等人，物理修订版信函${\bf 110}$，153602（2013）]。有效折射率及其方向和偏振依赖性与经典有效介质理论相同。作为我们的主要结果，我们推导出被动和主动介质的有效噪声光子分布的值也取决于光的偏振和传播方向。有趣的是，对于TE-偏振光入射到无源超材料上，噪声光子分布减少到热分布，但对于TM-偏振光，它不是。我们说明了我们的量子光学有效介质理论的鲁棒性的准确预测功率谱和平衡零差检测的超材料的输出量子态。
