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A Novel Dielectric Anomaly in Cuprates and Nickelates: Signature of an Electronic Glassy State

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 Added by Tuson Park
 Publication date 2004
  fields Physics
and research's language is English




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The low-frequency dielectric response of hole-doped insulators La_{2}Cu_{1-x}Li_{x}O_{4} and La_{2-x}Sr_{x}NiO_{4} shows a large dielectric constant epsilon ^{} at high temperature and a step-like drop by a factor of 100 at a material-dependent low temperature T_{f}. T_{f} increases with frequency and the dielectric response shows universal scaling in a Cole-Cole plot, suggesting that a charge glass state is realized both in the cuprates and in the nickelates.



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