Transformation-optical design of adaptive beam bends and beam expanders

TitleTransformation-optical design of adaptive beam bends and beam expanders
Publication TypeJournal Article
Year of Publication2008
AuthorsM.. Rahm, D..A. Roberts, J..B. Pendry, D.R. Smith
JournalOptics Express
Volume16
Issue15
Pagination11555-11567
ISBN Number1094-4087
Accession NumberWOS:000258069100079
Abstract

We describe the design of adaptive beam bends and beam splitters with arbitrary bend and split angles by use of finite embedded coordinate transformations. The devices do not exhibit reflection at the entrance or exit surfaces. It is shown that moderate and practically achievable values of the relative permittivity and permeability can be obtained for beam bends and splitters with both small and large bend radius. The devices are also discussed in the context of reconfigurable metamaterials, in which the bend and split angles can be dynamically tuned. The performance of adaptive beam bends and splitters is demonstrated in full wave simulations based on a finite-element method. Furthermore, the design of an adaptively adjustable transformation-optical beam expander/compressor is presented. It is observed that a pure transformation-optical design cannot result in a reflectionless beam expander/compressor. (c) 2008 Optical Society of America.