Abstract
Coordinate transformations are a versatile tool to mold the flow of light, enabling a host of astonishing phenomena such as optical cloaking with metamaterials. Moving away from the usual restriction that links isotropic materials with conformal transformations, we show how nonconformal distortions of optical space are intimately connected to the complex refractive index distribution of an isotropic non-Hermitian medium. Remarkably, this insight can be used to circumvent the material requirement of working with refractive indices below unity, which limits the applications of transformation optics. We apply our approach to design a broadband unidirectional dielectric cloak, which relies on nonconformal coordinate transformations to tailor the non-Hermitian refractive index profile around a cloaked object. Our insights bridge the fields of two-dimensional transformation optics and non-Hermitian photonics.
| Original language | English |
|---|---|
| Article number | 183901 |
| Number of pages | 6 |
| Journal | Physical review letters |
| Volume | 128 |
| Issue number | 18 |
| DOIs | |
| Publication status | Published - 6 May 2022 |
Funding
The work of I. K. was funded by the Austrian Science Fund (FWF) Lise Meitner Postdoctoral Fellowship M3011 and the FWF Grant No. P32300. The joint work of I. K., K. G. M., and S. R. was supported by the European Commission Grant No. MSCA-RISE 691209. U. L. was supported by the Israel Science Foundation and the Murray B. Koffler Professorial Chair. The computational results presented here have been obtained using the Vienna Scientific Cluster (VSC).