Broadband gradient index microwave quasi-optical elements based on non-resonant metamaterials

TitleBroadband gradient index microwave quasi-optical elements based on non-resonant metamaterials
Publication TypeJournal Article
Year of Publication2009
AuthorsR..P. Liu, Q.. Cheng, J..Y. Chin, J.J. Mock, T..J. Cui, D.R. Smith
JournalOptics Express
Volume17
Issue23
Pagination21030-21041
ISBN Number1094-4087
Accession NumberWOS:000271630000051
Abstract

Utilizing non-resonant metamaterial elements, we demonstrate that complex gradient index optics can be constructed exhibiting low material losses and large frequency bandwidth. Although the range of structures is limited to those having only electric response, with an electric permittivity always equal to or greater than unity, there are still numerous metamaterial design possibilities enabled by leveraging the non-resonant elements. For example, a gradient, impedance matching layer can be added that drastically reduces the return loss of the optical elements due to reflection. In microwave experiments, we demonstrate the broadband design concepts with a gradient index lens and a beam-steering element, both of which are confirmed to operate over the entire X-band ( roughly 812 GHz) frequency spectrum. (C) 2009 Optical Society of America