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Observation of supersymmetric pseudo-Landau levels in strained microwave graphene.

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 strengths. This result is achieved by utilising 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 the 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 polarisation of the anomalous 0th pseudo-Landau level, which reveals a deep connection to zigzag edge states in the unstrained case.

SUBMITTER: Bellec M

PROVIDER: S-EPMC7438506 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Observation of supersymmetric pseudo-Landau levels in strained microwave graphene.

Bellec Matthieu M Poli Charles C Kuhl Ulrich U Mortessagne Fabrice F Schomerus Henning H

Light, science & applications 20200819

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 strengths. This result is achieved by utilising 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 the fully formed flat-band pseudo-Landau levels spectrally as sharp peaks in the p ...[more]

PMID: 32864121

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