Critical States Embedded in the Continuum

Light Propagation in Non-Hermitian Optical Structures

“…Furthermore, we show that a family of critical modes with logarithmic scaling emerges at this transition point. These results have been published in our recent paper in reference [1].…”

“…In fact, We observe that before a threshold value for our Non-Hermitian defect, the eigenstates of the system are extended, while they happen to reorganize in the form of exponentially localized ones as soon as we pass the critical point. Furthermore, we can turn CSC into bound states in the continuum (BIC) by adding a uniform gain or loss background to all the WG's [1].…”

“…Instead, the collective response of this composite arrangement of metamaterials at the macroscopic level defines a homogeneous effective permittivity and permeability. 1 This allows us to engineer an unprecedented class of materials based on the needs of science and technology. Following this idea along with the recent developments in nanoscale fabrication in the field of optical science during the past decade have enabled us to create and manipulate materials with exotic features by having access to all four quadrants of permittivity-permeability plane.…”