Topological Transitions with an Imaginary Aubry-Andre-Harper Potential

Abstract

We study one-dimensional lattices with imaginary-valued Aubry-Andre-Harper (AAH) potentials. Such lattices can host edge states with purely imaginary eigenenergies, which differ from the edge states of the Hermitian AAH model and are stabilized by a non-Hermitian particle-hole symmetry. The edge states arise when the period of the imaginary potential is a multiple of four lattice constants. They are topological in origin, and can manifest on domain walls between lattices with different modulation periods and phases, as predicted by a bulk polarization invariant. Interestingly, the edge states persist and remain localized even if the real line gap closes. These features can be used in laser arrays to select topological lasing modes under spatially extended pumping.

References in corpus (15)

• Electric Multipole Moments, Topological Multipole Moment Pumping, and Chiral Hinge States in Crystalline Insulators
• Edge Modes, Degeneracies, and Topological Numbers in Non-Hermitian Systems
• Topological phases in the non-Hermitian Su-Schrieffer-Heeger model
• Topological phase transition in non-Hermitian quasicrystals
• Observation of Topological Phase Transitions in Photonic Quasicrystals
• Topological Pumping over a Photonic Fibonacci Quasicrystal
• Topological invariance and global Berry phase in non-Hermitian systems
• Phase transitions in a non-Hermitian Aubry-André-Harper model
• Symmetry-protected zero-mode laser with a tunable spatial profile
• Mode-Locked Topological Insulator Laser Utilizing Synthetic Dimensions
• Room temperature electrically pumped topological insulator lasers
• Numerical calculation of the complex berry phase in non-Hermitian systems
• Polarization and entanglement spectrum in non-hermitian systems
• PT-symmetric optical superlattices
• Electric polarization and its quantization in one-dimensional non-Hermitian chains

Cited by in corpus (7)

• Non-Hermitian topology and criticality in photonic arrays with engineered losses
• Versatile Braiding of Non-Hermitian Topological Edge States
• Localization and mobility edges in non-Hermitian continuous quasiperiodic systems
• Convection-modulated topological edge mode and extended-localized criticality in thermal metamaterials
• Topological Anderson insulator phases in one dimensional quasi-periodic mechanical SSH chains
• Topology and criticality in non-Hermitian multimodal optical resonators through engineered losses
• Dissipation induced ergodic-nonergodic transitions in finite-height mosaic Wannier-Stark lattices