Photonic topological insulators induced by non-Hermitian disorders in a coupled-cavity array
Abstract
Recent studies of disorder or non-Hermiticity induced topological insulators inject new ingredients for engineering topological matter. Here, we consider the effect of purely non-Hermitian disorders, a combination of these two ingredients, in a 1D coupled-cavity array with disordered gain and loss. Topological photonic states can be induced by increasing gain-loss disorder strength with topological invariants carried by localized states in the complex bulk spectra. The system showcases rich phase diagrams and distinct topological states from Hermitian disorders. The non-Hermitian critical behavior is characterized by the biorthogonal localization length of zero-energy edge modes, which diverges at the critical transition point and establishes the bulk-edge correspondence. Furthermore, we show that the bulk topology may be experimentally accessed by measuring the biorthogonal chiral displacement, which can be extracted from a proper Ramsey interferometer that works in both clean and disordered regions. The proposed coupled-cavity photonic setup relies on techniques that have been experimentally demonstrated and, thus, provides a feasible route toward exploring such non-Hermitian disorder driven topological insulators.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 21, 2023
- Source ID
- 10.1063/5.0153523
Entities
People
- Chuanwei Zhang
- Xi-Wang Luo
Organizations
- Air Force Office of Scientific Research
- CAS Key Laboratory of Quantum Information
- National Natural Science Foundation of China
- National Science Foundation
- University of Science and Technology of China
- University of Texas at Dallas