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Spin pseudogap in the $S=frac{1}{2}$ chain material Sr$_2$CuO$_3$ with impurities

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 نشر من قبل Gediminas Simutis
 تاريخ النشر 2016
  مجال البحث فيزياء
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The low energy magnetic excitation spectrum of the Heisenberg antiferromagnetic $S = 1/2$ chain system Sr$_2$CuO$_3$ with Ni- and Ca-impurities is studied by neutron spectroscopy. In all cases, a defect-induced spectral pseudogap is observed and shown to scale proportionately to the number of scattering centers in the spin chains.



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