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Asymmetric Field Profile in Bose Glass Phase of Irradiated YBa2Cu3O7-d: Loss of Interlayer Coherence around 1/3 of Matching Field

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 نشر من قبل Kenji Itaka
 تاريخ النشر 2001
  مجال البحث فيزياء
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Magneto-optical imaging in YBa2Cu3O7-d with tilted columnar defects (CDs) shows an asymmetric critical-state field profile. The observed hysteretic shift of the profile ridge (trough) from the center of the sample is explained by in-plane magnetization originated from vortex alignment along CDs. The extracted ratio of the in-plane to out-of-plane magnetization component has a maximum at 1/5 of matching field ($B_Phi$) and disappears above $B_Phi/3$, suggesting a reduction of interlayer coherence well bellow $B_Phi$ in the Bose glass phase. Implications are discussed in comparison with the vortex liquid recoupling observed in irradiated Bi2Sr2CaCu2O8+y.



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