Room-temperature transport of indirect excitons in (Al,Ga)N/GaN quantum wells

  title={Room-temperature transport of indirect excitons in (Al,Ga)N/GaN quantum wells},
  author={Fedor Fedichkin and Thierry Guillet and Pierre Valvin and B. Jouault and C. Brimont and Thierry Bretagnon and L. Lahourcade and Nicolas Grandjean and P. Lefebvre and Maria Vladimirova},
  journal={arXiv: Mesoscale and Nanoscale Physics},
We report on the exciton propagation in polar (Al,Ga)N/GaN quantum wells over several micrometers and up to room temperature. The key ingredient to achieve this result is the crystalline quality of GaN quantum wells (QWs) grown on GaN template substrate. By comparing microphotoluminescence images of two identical QWs grown on sapphire and on GaN, we reveal the twofold role played by GaN substrate in the transport of excitons. First, the lower threading dislocation densities in such structures… 

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