1. University of Edinburgh, School of Mathematics and Maxwell Institute for Mathematical Sciences, Edinburgh, Scotland, United KingdombPennsylvania State University, Department of Engineering Science and Mechanics, NanoMM—Nanoengineered Metamaterials Group, University Park, Pennsylvania, United States
2. Pennsylvania State University, Department of Engineering Science and Mechanics, NanoMM—Nanoengineered Metamaterials Group, University Park, Pennsylvania, United States