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Excitonic insulators as a model of $d-d$ and Mott transitions in strongly correlated materials

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 نشر من قبل Robert Markiewicz
 تاريخ النشر 2017
  مجال البحث فيزياء
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We show how strongly correlated materials could be described within the framework of an excitonic insulator formalism, and delineate the relationship between inter- and intra-band ordering phenomena. Our microscopic model of excitons clarifies the fundamental role of Van-Hove-singularity-nesting in driving both inter- and intra-band ordering transitions, and uncovers an interesting connection with resonating-valence-bond physics.

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