Scattering properties of PT-symmetric layered periodic structures

Abstract

The optical properties of PT-symmetric periodic stack of the layers with balanced loss and gain are examined. We demonstrate that tunnelling phenomenon in periodic structures is connected with excitation of surface waves at the boundaries separating gain and loss regions within each unit cell and tunnelling conditions for periodic stack can be reduced to the conditions for one period. Alternatively, it is shown that coherent perfect absorber laser states are mediated by excitation of surface modes localised at all internal boundaries of the structure. The effects of the structure parameters and angle and direction of incidence on the resonant phenomena and spontaneous symmetry breaking transition are determined. It is shown that structure periodicity significantly increases the number of resonant phenomena, especially in stacks with high real and imaginary parts of dielectric permittivity of the layers. Gaussian beam dynamics in this type of structure is examined. The beam splitting in PT-symmetric periodic structure is observed.

14 pages, 10 figures, journal paper. arXiv admin note: text overlap with arXiv:1505.02523

References in corpus (6)

• Physical realization of $\mathcal{P}\mathcal{T}$-symmetric potential scattering in a planar slab waveguide
• Exponentially Fragile PT-Symmetry in Lattices with Localized Eigenmodes
• Gain-Driven Discrete Breathers in PT-Symmetric Nonlinear Metamaterials
• PT-Symmetric Talbot Effects
• Tunneling of Obliquely-Incident Waves through PT-Symmetric Epsilon-Near-Zero Bi-Layers
• PT-symmetry breaking with divergent potentials: lattice and continuum cases

Cited by in corpus (7)

• Chiral metamaterials with PT symmetry and beyond
• Scattering by finite periodic $\mathcal{P}\mathcal{T}$-symmetric structures
• PT-symmetric chiral metamaterials: Asymmetric effects and PT-phase control
• Non-Hermitian spectral changes in the scattering of partially coherent radiation by periodic structures
• Accessible phases via wave impedance engineering with PT-symmetric metamaterials
• Unidirectional reflectivity in non-Hermitian lossy thin films
• CPA-lasing associated with the quasibound states in the continuum in asymmetric non-Hermitian structures