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Spatial Coherence of a polariton condensate in 1D acoustic lattice

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 نشر من قبل Oleksandr Tsyplyatyev
 تاريخ النشر 2012
  مجال البحث فيزياء
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Several mechanisms are discussed which could determine the spatial coherence of a polariton condensate confined to a one dimensional wire. The mechanisms considered are polariton-polariton interactions, disorder scattering and non-equilibrium occupation of finite momentum modes. For each case, the shape of the resulting spatial coherence function g1(x) is analysed. The results are compared with the experimental data on a polariton condensate in an acoustic lattice from [E. A. Cerda-Mendez et al, Phys. Rev. Lett. 105, 116402 (2010)]. It is concluded that the shape of g1(x) can only be explained by non-equilibrium effects, and that ~10 modes are occupied in the experimental system.



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