Topological edge states of the PT -symmetric Su-Schrieffer-Heeger model: An effective two-state description

We consider the non-Hermitian, parity-time (PT) symmetric extensions of the one-dimensional Su-Schrieffer-Heeger (SSH) model in the topological non-trivial configuration. We study the properties of the topologically protected edge states, and develop an effective two-state analytical description of the system that accurately predicts the PT-symmetry breaking point for the edge states. We verify our analytical results by exact numerical calculations.

[1]  A. Szameit,et al.  Nonlinear tuning of PT symmetry and non-Hermitian topological states , 2021, Science.

[2]  D. Leykam,et al.  Special Issue on “Topological photonics and beyond: novel concepts and recent advances” , 2020, Light, science & applications.

[3]  A. Szameit,et al.  Topological funneling of light , 2020, Science.

[4]  S. Longhi,et al.  Non-Hermitian topological light steering , 2019, Science.

[5]  F. Nori,et al.  Parity–time symmetry and exceptional points in photonics , 2019, Nature Materials.

[6]  J. E. Barrios Vargas,et al.  Topological states of non-Hermitian systems , 2018, The European Physical Journal Special Topics.

[7]  M. Bandres,et al.  Topological insulator laser: Theory , 2018, Science.

[8]  M. Bandres,et al.  Topological insulator laser: Experiments , 2018, Science.

[9]  Teresa J. Feo,et al.  Structural absorption by barbule microstructures of super black bird of paradise feathers , 2018, Nature Communications.

[10]  Demetrios N. Christodoulides,et al.  Non-Hermitian physics and PT symmetry , 2018, Nature Physics.

[11]  M Segev,et al.  Topologically protected bound states in photonic parity-time-symmetric crystals. , 2017, Nature materials.

[12]  M. Soljačić,et al.  Topological photonics , 2014, Nature Photonics.

[13]  V. Konotop,et al.  Nonlinear modes in a generalized PT?>-symmetric discrete nonlinear Schrödinger equation , 2013, 1310.5651.

[14]  Felix Dreisow,et al.  Photonic Floquet topological insulators , 2012, Nature.

[15]  D. Pesin,et al.  Spintronics and pseudospintronics in graphene and topological insulators. , 2012, Nature materials.

[16]  M. Segev,et al.  Observation of parity–time symmetry in optics , 2010 .

[17]  L. Molenkamp,et al.  Quantum Spin Hall Insulator State in HgTe Quantum Wells , 2007, Science.

[18]  X. Wen.  Topological orders and edge excitations in fractional quantum hall states , 1995, cond-mat/9506066.

[19]  W. B. Thompson,et al.  What is light? , 2008, Discovering Light: Fun Experiments with Optics.

[20]  John K. Tomfohr,et al.  Lecture Notes on Physics , 1879, Nature.