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arXiv · 2209.10745

Experimental realization of chiral Landau levels in two-dimensional Dirac cone systems with inhomogeneous effective mass

Hongwei Jia·Mudi Wang·Shaojie Ma·Ruo-Yang Zhang·Jing Hu·C. T. Chan
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Abstract

Chiral zeroth Landau levels are topologically protected bulk states that give rise to chiral anomaly. Previous discussions on such chiral Landau levels are based on three-dimensional Weyl degeneracies. Their realizations using two-dimensional Dirac point systems, being more promising for future applications, were never reported before. Here we propose a theoretical and experimental scheme for realizing chiral Landau levels in a photonic system. By introducing an inhomogeneous effective mass through breaking local parity inversion symmetries, the zeroth-order chiral Landau levels with one-way propagation characteristics are experimentally observed. In addition, the robust transport of the chiral zeroth mode against defects in the system is experimentally tested. Our system provides a new pathway for the realization of chiral Landau levels in two-dimensional Dirac systems, and may potentially be applied in device designs utilizing the transport robustness.

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Hongwei Jia, Mudi Wang, Shaojie Ma, Ruo-Yang Zhang, Jing Hu, C. T. Chan. 2022-09-22. Experimental realization of chiral Landau levels in two-dimensional Dirac cone systems with inhomogeneous effective mass. https://doi.org/10.1038/s41377-023-01209-z

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