PT-symmetric non-Hermitian AB-stacked bilayer honeycomb photonic lattice

Abstract

We theoretically investigate the band structure of the parity-time ( P T )-symmetric non-Hermitian bilayer honeycomb photonic lattice by considering the co-existence of onsite energy detuning and P T -symmetric imaginary potentials. It is found that P T symmetry causes the system’s energy spectra to display salient features, which include various energy-band degeneracies and deformation of the band structure in the vicinity of the Dirac point. Also, the P T -symmetry breaking can be modulated by introducing strain to the system. The findings in this work can help in understanding the band structures of P T -symmetric bilayer honeycomb photonic-lattice systems.

Topological Photonic Crystals: Physics, Designs, and Applications

“…For example, non-Hermitian topological photonic systems are attracting more and more interests of researchers. [383][384][385][386][387][388][389][390][391][392] The combination of non-Hermitian and topological physics inspires the observation of intriguing phenomena and practical applications. For another example, the real-space lattice defects in topological systems have also inspired the interests of researchers recently.…”

Topology of a parity–time symmetric non-Hermitian rhombic lattice

“…In recent years, parity-time (𝒫𝒯 ) symmetry has attracted increasing attention in non-Hermitian quantum mechanics. [1][2][3][4][5][6][7][8][9][10][11] 𝒫𝒯 -symmetric non-Hermitian systems, which may possess entirely real spectra, [12] have been widely explored in the optical waveguides, resonators, and cold atoms in optical lattices. The exceptional point (EP), known as the 𝒫𝒯 -symmetric phase transition point, indicates the transition between the exact 𝒫𝒯 -symmetric phase and the broken 𝒫𝒯symmetric phase.…”