Abstract
Luneburg lens and Maxwell-fisheye lens are well-known microwave and optical devices with distinct focusing properties. Here, a planar bifunctional Luneburg-fisheye lens made of an anisotropic metasurface is presented, which features as a Luneburg along the horizontal optical axis, while as a fisheye along the vertical optical axis. A method to control the inhomogeneous indices of refraction along the two optical axes independently is proposed by designing an anisotropic and nonuniform metasurface, which can provide the required distributions of refractive indices approximately for Luneburg and fisheye lenses viewing from the two optical axes. Experiments in the microwave frequency range demonstrate very good performance of the planar bifunctional Luneburg-fisheye lens. The proposed method opens up an avenue to design other kinds of bifunctional devices using metasurfaces in the microwave, terahertz, and even optical ranges.
Highlights
In the classical physics, Luneburg lens and Maxwell fisheye lens are two typical optical devices with the spherical symmetry
We apply for the above method to design an anisotropic metasurface which performs like the Luneburg lens in the horizontal optical axis and the Maxwell fisheye lens in the vertical optical axis
We have proposed a method to control the inhomogeneous refractive indexes independently along two optical axes by designing the anisotropic and non-uniform metasurface
Summary
Luneburg lens and Maxwell fisheye lens are two typical optical devices with the spherical symmetry. We notice that the current designs of bulk metamaterials and planar metasurfaces are still difficult to control anisotropic and inhomogeneous distributions of material parameters independently along two optical axes.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
