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Charged bosons made of fermions in a solid state system without Cooper pairing

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 نشر من قبل Zheng Sun
 تاريخ النشر 2020
  مجال البحث فيزياء
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We report experimental evidence for charged boson states in a solid without Cooper pairing, based on attaching two free carriers to an exciton in a semiconducting system. Theoretical calculations show that this type of complex is stable in bilayer systems next to a parallel metal layer. Our experimental measurements on structures made using two different materials show a new spectral line at the predicted energy, if and only if all the required conditions for this complex are fulfilled, including a parallel metal layer that significantly screens the repulsive interaction between the like-charge carriers, and with the predicted dependence on the distance to the metal layer. This suggests a new path for pursuing room temperature superconductivity without Cooper pairing.



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