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Experimental determination of B-T phase diagram of YBa_2Cu_3O_7-d to 150T for B perpendicular to c

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 نشر من قبل Jeremy L. O'Brien
 تاريخ النشر 1999
  مجال البحث فيزياء
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The B-T phase diagram for thin film YBa_2Cu_3O_7-d with B parallel to the superconducting layers has been constructed from GHz transport measurements to 150T. Evidence for a transition from a high T regime dominated by orbital effects, to a low T regime where paramagnetic limiting drives the quenching of superconductivity, is seen. Up to 110T the upper critical field is found to be linear in T and in remarkable agreement with extrapolation of the longstanding result of Welp et al arising from magnetisation measurements to 6T. Beyond this a departure from linear behaviour occurs at T=74K, where a 3D-2D crossover is expected to occur.



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