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Observation and characterization of a non-Abelian gauge fields Wilczek-Zee phase by the Wilson loop

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 نشر من قبل Seiji Sugawa
 تاريخ النشر 2019
  مجال البحث فيزياء
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Quantum states can acquire a phase called the Berry phase after adiabatically traversing a closed loop in parameter space. This phase is geometric -- dependent on the path -- not the rate of motion. Wilczek and Zee extended this concept to include non-Abelian phases that can be characterized the Wilson loop, a gauge independent quantity. Here we quantum-engineer a non-Abelian SU(2) gauge field for an atomic Bose-Einstein Condensate (BEC), in a 5-dimensional synthetic parameter space derived from internal atomic degrees of freedom. By slowly encircling a topological monopole, we observed the adiabatic Wilczek-Zee phase that we characterize in terms of the Wilson loop.



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