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arXiv · 2101.05294

Quantum oscillations in the zeroth Landau Level and the serpentine Landau fan

T. Devakul·Yves H. Kwan·S. L. Sondhi·S. A. Parameswaran
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Abstract

We identify an unusual mechanism for quantum oscillations in nodal semimetals, driven by a single pair of Landau levels periodically closing their gap at the Fermi energy as a magnetic field is varied. These `zero Landau level' quantum oscillations (ZQOs) appear in the nodal limit where the zero-field Fermi volume vanishes, and have distinctive periodicity and temperature dependence. We link the Landau spectrum of a two-dimensional (2D) nodal semimetal to the Rabi model, and show by exact solution that across the entire Landau fan, pairs of opposite-parity Landau levels are intertwined in a `serpentine' manner. We propose 2D surfaces of topological crystalline insulators as natural settings for ZQOs, and comment on implications for anomaly physics in 3D nodal semimetals.

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T. Devakul, Yves H. Kwan, S. L. Sondhi, S. A. Parameswaran. 2021-08-10. Quantum oscillations in the zeroth Landau Level and the serpentine Landau fan. https://doi.org/10.1103/physrevlett.127.116602

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