Su-Schrieffer-Heeger chain with one pair of PT-symmetric defects

Abstract

The topologically nontrivial edge states induce PT transition in Su-Schrieffer-Heeger (SSH) chain with one pair of gain and loss at boundaries. In this study, we investigated a pair of PT-symmetric defects located inside the SSH chain, in particular, the defects locations are at the chain centre. The PT symmetry breaking of the bound states leads to the PT transition, the PT-symmetric phases and the localized states were studied. In the broken PT-symmetric phase, all energy levels break simultaneously in topologically trivial phase; however, two edge states in topologically nontrivial phase are free from the influence of the PT-symmetric defects. We discovered PT-symmetric bound states induced by the PT-symmetric local defects at the SSH chain centre. The PT-symmetric bound states significantly increase the PT transition threshold and coalesce to the topologically protected zero mode with vanishing probabilities on every other site of the left-half chain and the right-half chain, respectively.

9 pages, 5 figures,

References in corpus (13)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Loss-induced suppression and revival of lasing
• Visualization of Branch Points in PT-Symmetric Waveguides
• Edge Modes, Degeneracies, and Topological Numbers in Non-Hermitian Systems
• PT-Symmetric Phonon Laser
• Selective enhancement of topologically induced interface states in a dielectric resonator chain
• Faster than Hermitian Quantum Mechanics
• Exponentially Fragile PT-Symmetry in Lattices with Localized Eigenmodes
• Optomechanically-Induced Transparency in partiy-time-symmetric microresonators
• PT-Symmetry in Non-Hermitian Su-Schrieffer-Heeger model with complex boundary potentials
• Topological phase in a non-Hermitian PT symmetric system
• Tip induced unconventional superconductivity on Weyl semimetal TaAs
• Zero modes, energy gap, and edge states of anisotropic honeycomb lattice in a magnetic field

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• Non-Hermitian phase transition and eigenstate localization induced by asymmetric coupling
• Compatibility of transport effects in non-Hermitian nonreciprocal systems
• Spontaneous topological pumping in non-Hermitian systems
• Fast quantum transfer mediated by topological domain walls
• Robust localized zero-energy modes from locally embedded PT-symmetric defects
• Reservoir-assisted symmetry breaking and coalesced zero-energy modes in an open PT-symmetric Su-Schrieffer-Heeger model
• Topological triple phase transition in non-Hermitian quasicrystals with complex asymmetric hopping
• Topological phases of commensurate or incommensurate non-Hermitian Su-Schrieffer-Heeger lattices
• Topology of multiple cross-linked Su-Schrieffer-Heeger chains
• Emergence of Exceptional Points in Periodic Metastructures with Hidden PT-symmetric Defects
• Braids and Higher-order Exceptional Points from the Interplay Between Lossy Defects and Topological Boundary States
• Berry curvature inside parity-time-symmetry protected exceptional surface
• Topological states at exceptional points
• Dynamic transition from insulating state to eta-pairing state in a composite non-Hermitian system
• Non-Hermitian tuned topological band gap
• Topological split-ring resonator based metamaterials with $\mathcal{P}\mathcal{T}$ symmetry relying on gain and loss