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Localization of light in a three-dimensional disordered crystal of atoms

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 نشر من قبل Sergey E Skipetrov
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف S.E. Skipetrov




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We demonstrate that a weak disorder in atomic positions introduces spatially localized optical modes in a dense three-dimensional ensemble of immobile two-level atoms arranged in a diamond lattice and coupled by the electromagnetic field. The frequencies of the localized modes concentrate near band edges of the unperturbed lattice. Finite-size scaling analysis of the percentiles of Thouless conductance reveals two mobility edges and yields an estimation $ u = 0.8$--1.1 for the critical exponent of the localization length. The localized modes disappear when the disorder becomes too strong and the system starts to resemble a fully disordered one where all modes are extended.



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