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Nature of Orbital Ordering in La_0.5Sr_1.5MnO_4 is Studied by Soft X-ray Linear Dichroism

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 Added by Di-Jing Huang
 Publication date 2003
  fields Physics
and research's language is English




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We found that the conventional model of orbital ordering of 3x^2-r^2/3y^2-r^2 type in the eg states of La_0.5Sr_1.5MnO_4 is incompatible with measurements of linear dichroism in the Mn 2p-edge x-ray absorption, whereas these eg states exhibit predominantly cross-type orbital ordering of x^2-z^2/y^2-z^2. LDA+U band-structure calculations reveal that such a cross-type orbital ordering results from a combined effect of antiferromagnetic structure, Jahn-Teller distortion, and on-site Coulomb interactions.



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