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LaFeAsO$_{1-x}$F$_{x}$ thin films: high upper critical fields and evidence of weak link behavior

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 نشر من قبل Martin Kidszun
 تاريخ النشر 2009
  مجال البحث فيزياء
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High-quality superconducting LaFeAsO$_{1-x}$F$_{x}$ thin films were grown on single crystalline LaAlO$_{3}$ substrates with critical temperatures (onset) up to 28 K. Resistive measurements in high magnetic fields up to 40 T reveal a paramagnetically limited upper critical field, $mu_{0}H_{c2}$(0) around 77 T and a remarkable steep slope of -7.5 T/K near $T_{c}$. From transport measurements we observed a weak link behavior in low magnetic fields and the evidence for a broad reversible regime.



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