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Floquet Engineering Topological Dirac Bands.

ABSTRACT: We experimentally realized a time-periodically modulated 1D lattice for ultracold atoms featuring a pair of linear bands, each with a Floquet winding number. These bands are spin-momentum locked and almost perfectly linear everywhere in the Brillouin zone: a near-ideal realization of the 1D Dirac Hamiltonian. We characterized the Floquet winding number using a form of quantum state tomography, covering the Brillouin zone and following the micromotion through one Floquet period. Last, we altered the modulation timing to lift the topological protection, opening a gap at the Dirac point that grew in proportion to the deviation from the topological configuration.

SUBMITTER: Lu M

PROVIDER: S-EPMC9832990 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Floquet Engineering Topological Dirac Bands.

Lu Mingwu M Reid G H GH Fritsch A R AR Piñeiro A M AM Spielman I B IB

Physical review letters 20220701 4

We experimentally realized a time-periodically modulated 1D lattice for ultracold atoms featuring a pair of linear bands, each with a Floquet winding number. These bands are spin-momentum locked and almost perfectly linear everywhere in the Brillouin zone: a near-ideal realization of the 1D Dirac Hamiltonian. We characterized the Floquet winding number using a form of quantum state tomography, covering the Brillouin zone and following the micromotion through one Floquet period. Last, we altered ...[more]

PMID: 35939027

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