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Emergent units of itinerant spin-state excitations in LaCoO$_3$

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 نشر من قبل Keisuke Tomiyasu
 تاريخ النشر 2018
  مجال البحث فيزياء
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Spin crossover is expected to enrich unusual physical states in various types of condensed matter. Through inelastic neutron scattering, we study the spin-state excitations in the canonical and advanced platform, LaCoO$_3$, and reveal that the spatial correlation robustly maintains the seven-Co-site size below 300 K and the internal Co-$d$ electrons are spatially delocalized. By combining theoretical calculations, this dynamical short-range order is identified as a new collective unit for describing spin-state with dual spin-state nature beyond the conventional one-Co-site classification.

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