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Realizing Landau levels with open equifrequency contours around band singularities
Cuicui Lu1,2, Oubo You3, Yanji Zheng4
1Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education, State Key Laboratory of Chips and Systems for Advanced Light Field Display, Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, Center for Interdisciplinary Science of Optical Quantum and NEMS Integration, School of Physics, Beijing Institute of Technology, Beijing, China. cuicuilu@bit.edu.cn.
Nature Communications
|April 4, 2026
Summary
Researchers demonstrate Landau levels (LLs) in systems with open equifrequency contours (EFCs) using combined electric and magnetic fields. This breakthrough enables LLs in new systems, advancing optical wave control.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Metamaterials Science
Background:
- Charged particles in magnetic fields exhibit quantized energy levels known as Landau levels (LLs).
- LLs near band singularities possess nontrivial topological properties.
- Previous observations of LLs were limited to systems with closed equifrequency contours (EFCs) around band singularities, such as type-I Dirac or Weyl systems.
Purpose of the Study:
- To demonstrate the existence of LLs in systems with open EFCs around band singularities.
- To investigate the role of combined artificial electric (E) and magnetic (B) fields in generating LLs.
- To provide a new platform for controlling optical wave propagation using artificial gauge fields.
Main Methods:
- Construction of an artificial platform using inhomogeneous metasurfaces of a two-dimensional type-II Dirac system.
- Creation of artificial gauge fields incorporating both electric (E) and magnetic (B) fields.
- Experimental observation of emergent E&B-induced Landau levels.
Main Results:
- Landau levels (LLs) were successfully generated in a system with open equifrequency contours (EFCs).
- The combined action of artificial electric and magnetic fields was crucial for generating these LLs, which are not achievable with magnetic fields alone.
- Experimental evidence confirmed the emergence of E&B-induced LLs.
Conclusions:
- This study presents a novel approach for realizing Landau levels in systems previously thought incapable of supporting them.
- The findings offer new insights into the topological properties of band singularities and LLs.
- The developed artificial platform provides a versatile tool for manipulating optical wave propagation via artificial gauge fields.
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