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arXiv · 2001.10287

Observation of supersymmetric pseudo-Landau levels in strained microwave graphene

Matthieu Bellec·Charles Poli·Ulrich Kuhl·Fabrice Mortessagne·Henning Schomerus
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Abstract

Using an array of coupled microwave resonators arranged in a deformed honeycomb lattice, we experimentally observe the formation of pseudo-Landau levels in the whole crossover from vanishing to large pseudomagnetic field strength. This is achieved by utilizing an adaptable set-up in a geometry that is compatible with the pseudo-Landau levels at all field strengths. The adopted approach enables to observe fully formed flat-band pseudo-Landau levels spectrally as sharp peaks in the photonic density of states, and image the associated wavefunctions spatially, where we provide clear evidence for a characteristic nodal structure reflecting the previously elusive supersymmetry in the underlying low-energy theory. In particular, we resolve the full sublattice polarization of the anomalous 0th pseudo-Landau level, which reveals a deep connection to zigzag edge states in the unstrained case.

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Matthieu Bellec, Charles Poli, Ulrich Kuhl, Fabrice Mortessagne, Henning Schomerus. 2020-01-28. Observation of supersymmetric pseudo-Landau levels in strained microwave graphene. https://doi.org/10.1038/s41377-020-00351-2

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