Related Experiment Video
Updated: Jul 31, 2025
09:00
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Non-Hermitian topological phases: principles and prospects
Ayan Banerjee1, Ronika Sarkar1,2, Soumi Dey1
1Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India.
Summary
This review explores non-Hermitian topology, merging non-Hermitian physics and topological concepts. It details key principles, models, and phenomena like the non-Hermitian skin effect, advancing understanding of these complex systems.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Topological Materials
Background:
- Recent years have seen significant synergy between non-Hermitian concepts and topological ideas.
- This interplay has unveiled a diverse range of novel non-Hermitian topological phenomena.
Purpose of the Study:
- To present the fundamental principles governing the topological characteristics of non-Hermitian phases.
- To illustrate key features of non-Hermitian topological systems using established models.
Main Methods:
- Utilized paradigmatic models: Hatano-Nelson, non-Hermitian Su-Schrieffer-Heeger, and non-Hermitian Chern insulator.
- Discussed concepts such as exceptional points, complex energy gaps, and non-Hermitian symmetry classification.
- Examined the non-Hermitian skin effect and generalized Brillouin zone for bulk-boundary correspondence.
Main Results:
- Illustrated central features of non-Hermitian topological systems, including exceptional points and complex energy gaps.
- Addressed the non-Hermitian skin effect and its implications for bulk-boundary correspondence.
- Analyzed the impact of disorder, Floquet engineering, and linear response on Hall transport properties.
Conclusions:
- Summarized key principles and phenomena in non-Hermitian topological systems.
- Surveyed recent experimental advancements in the field.
- Highlighted promising future research directions in non-Hermitian topology.
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