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High temperature electron-hole superfluidity with strong anisotropic gaps in double phosphorene monolayers

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 نشر من قبل Mohammad Zarenia
 تاريخ النشر 2018
  مجال البحث فيزياء
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Excitonic superfluidity in double phosphorene monolayers is investigated using the BCS mean-field equations. Highly anisotropic superfluidity is predicted where we found that the maximum superfluid gap is in the BEC regime along the armchair direction and in the BCS-BEC crossover regime along the zigzag direction. We estimate the highest Kosterlitz-Thouless transition temperature with maximum value up to $sim 90$ K with onset carrier densities as high as $4 times 10^{12}$ cm$^{-2}$. This transition temperature is significantly larger than what is found in double electron-hole few-layers of graphene. Our results can guide experimental research towards the realization of anisotropic condensate states in electron-hole phosphorene monolayers.



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