Generalized Maxwell Fish-Eye Lens as a Beam Splitter: A Case Study in Realizing All-Dielectric Devices From Transformation Electromagnetics

Qin Lei, Robert Foster, Patrick S. Grant, Chris Grovenor
  • IEEE Transactions on Microwave Theory and Techniques, January 2017, Institute of Electrical & Electronics Engineers (IEEE)
  • DOI: 10.1109/tmtt.2017.2727495

Making devices requiring material properties that vary with position using composite dielectrics

What is it about?

"Transformation Electromagnetics" is a mathematical technique for designing electromagnetic devices with different functions. This technique results in a device that uses the variation of material properties with position (within the device boundaries) to achieve the required function. In this paper, we use a particular equation (the Generalised Maxwell Fish-Eye lens equation) to provide the spatial variation for achieving "beam splitting", where an input beam of light (in our case, a radio wave) is turned into two output beams. We then look at how composite dielectrics (non-metal mixtures) can be used to make this device and talk about the challenges in fabrication.

Why is it important?

Transformation Electromagnetics has been a topic of considerable interest over the last decade. It usually results in challenging material requirements that are often met using "metamaterials", which are artificial materials that derive their properties from the geometry of the constituents, as well as their chemical composition. However, these are typically narrow-bandwidth materials and broader bandwidths are possible using conventional composite dielectrics. Thus, materials scientists have been reexamining how to make such materials with the required control of the properties, as well as different fabrication techniques, including casting (as in this paper) and 3D printing (additive manufacturing). We show, using a particular device as an exemplar, progress in this area and discuss some of the challenges for transferring these techniques into industry.

Perspectives

Dr Robert N Foster
University of Birmingham

I'm quite pleased with this paper. I think we worked hard to understand the process and the problems encountered, and thus have developed a good insight into what is required to use "graded" composite dielectrics for complex electromagnetic devices. Although we used a surface wave device for the paper, bulk devices are also possible.

Read Publication

http://dx.doi.org/10.1109/tmtt.2017.2727495

The following have contributed to this page: Dr Robert N Foster