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A Possible Crypto-Superconducting Structure in a Superconducting Ferromagnet

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 نشر من قبل C. W. Chu
 تاريخ النشر 2000
  مجال البحث فيزياء
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 تأليف C. W. Chu




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We have measured the dc and ac electrical and magnetic properties in various magnetic fields of the recently reported superconducting ferromagnet RuSr2GdCu2O8. Our reversible magnetization measurements demonstrate the absence of a bulk Meissner state in the compound below the superconducting transition temperature. Several scenarios that might account for the absence of a bulk Meissner state, including the possible presence of a sponge-like non-uniform superconducting or a crypto-superconducting structure in the chemically uniform Ru-1212, have been proposed and discussed.


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