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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.
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This content will become publicly available on July 10, 2026
Robustness of the Floquet topological phase at room temperature: a first-principles dynamics study
Nonadiabatic Thouless pumping of electrons is studied within the framework of topological Floquet engineering, focused on how atomic lattice dynamics affect the emergent Floquet topological phase in polyacetylene under the driving electric field.
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- Award ID(s):
- 2209858
- PAR ID:
- 10617214
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 27
- Issue:
- 27
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 14410 to 14417
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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