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NMR study on the local structure in La-based high-Tc cuprates

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 نشر من قبل Takayuki Goto
 تاريخ النشر 2008
  مجال البحث فيزياء
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To date, there has been no evidence for the macroscopic structural phase transition to the low temperature tetragonal structure (LTT) with a space group P42/ncm in high-TC cuprate of rare earth-free La2-xSrxCuO4 (LSCO). By investigating Cu-NMR on single crystals, we have found that spatially incoherent LTT structure emerges below 50 K in the sample with x=0.12. This incoherent structure is considered to play a key role for the slight depression of the superconductivity around x=1/8.



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