Observation of supersymmetric pseudo-Landau levels in strained microwave graphene

Matthieu Bellec (1) , Charles Poli (2) , Ulrich Kuhl (1) , Fabrice Mortessagne (1) , Henning Schomerus (2)

1 INPHYNI - Institut de Physique de Nice
2 Department of Physics [Lancaster]

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 setup in a geometry that is compatible with the pseudo-Landau levels at all field strengths. The adopted approach enables us 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.

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Matthieu Bellec, Charles Poli, Ulrich Kuhl, Fabrice Mortessagne, Henning Schomerus. Observation of supersymmetric pseudo-Landau levels in strained microwave graphene. Light: Science and Applications, 2020, 9 (1), pp.146. ⟨10.1038/s41377-020-00351-2⟩. ⟨hal-02940060⟩