%A Yang-Yang Fu, Ya-Dong Xu, Huan-Yang Chen %T Negative refraction based on purely imaginary metamaterials %0 Journal Article %D 2018 %J Front. Phys. %J Frontiers of Physics %@ 2095-0462 %R 10.1007/s11467-018-0781-3 %P 134206- %V 13 %N 4 %U {https://journal.hep.com.cn/fop/EN/10.1007/s11467-018-0781-3 %8 2018-08-07 %X

By introducing a new mechanism based on purely imaginary metamaterials (PIMs), we reveal that bidirectional negative refraction and planar focusing can be obtained using a pair of PIM slabs, overcoming the unidirectional limit in parity-time (PT)-symmetric systems. Compared with PT-symmetric systems, which require two different types of materials, the proposed negative refraction can be realized using two identical media. In addition, asymmetric excitation with bidirectional total transmission is observed in our PIM system. Therefore, a new way to realize negative refraction with properties that are unavailable in PT-symmetric systems is presented.