Pancharatnam–Berry phase in condensate of indirect excitons

@article{Leonard2018PancharatnamBerryPI,
  title={Pancharatnam–Berry phase in condensate of indirect excitons},
  author={J R Leonard and Alexander A. High and Aaron Tynes Hammack and Michael M. Fogler and L V Butov and Kenneth Lee Campman and Arthur C. Gossard},
  journal={Nature Communications},
  year={2018},
  volume={9}
}
The Pancharatnam–Berry phase is a geometric phase acquired over a cycle of parameters in the Hamiltonian governing the evolution of the system. Here, we report on the observation of the Pancharatnam–Berry phase in a condensate of indirect excitons (IXs) in a GaAs-coupled quantum well structure. The Pancharatnam–Berry phase is directly measured by detecting phase shifts of interference fringes in IX interference patterns. Correlations are found between the phase shifts, polarization pattern of… 

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