Topological protection in non-Hermitian Haldane honeycomb lattices


Por: Reséndiz-Vázquez P., Tschernig K., Perez-Leija A., Busch K., León-Montiel R.D.J.

Publicada: 1 ene 2020
Resumen:
Topological phenomena in non-Hermitian systems have recently become a subject of great interest in the photonics and condensed-matter communities. In particular, the possibility of observing topologically protected edge states in non-Hermitian lattices has sparked an intensive search for systems where this kind of states are sustained. Here we present a study of the emergence of topological edge states in two-dimensional Haldane lattices exhibiting balanced gain and loss. In line with recent studies on other Chern insulator models, we show that edge states can be observed in the so-called broken PT-symmetric phase, that is, when the spectrum of the gain-loss-balanced system's Hamiltonian is not entirely real. More importantly, we find that such topologically protected edge states emerge irrespective of the lattice boundaries, namely, zigzag, bearded, or armchair. © 2020 authors. Published by the American Physical Society.

Filiaciones:
Reséndiz-Vázquez P.:
 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, Ciudad de México, 04510, Mexico

Tschernig K.:
 Max-Born-Institut, Max-Born-Straße 2A, Berlin, 12489, Germany

 Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik and Photonik, Berlin, D-12489, Germany

Perez-Leija A.:
 Max-Born-Institut, Max-Born-Straße 2A, Berlin, 12489, Germany

 Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik and Photonik, Berlin, D-12489, Germany

Busch K.:
 Max-Born-Institut, Max-Born-Straße 2A, Berlin, 12489, Germany

 Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik and Photonik, Berlin, D-12489, Germany

León-Montiel R.D.J.:
 Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, Ciudad de México, 04510, Mexico
ISSN: 26431564
Editorial
AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 2 Número: 1
Páginas:
imagen Gold