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Direct observation of quantized interlayer vortex flow and vortex pinning distribution in high-Tc La_(1.87)Sr_(0.13)CuO_4 single crystals

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 نشر من قبل Shunichi Arisawa
 تاريخ النشر 2007
  مجال البحث فيزياء
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A scanning superconducting quantum interference device (SQUID) microscope (SSM) is used to study the magnetic imaging of dynamic motion of quantized interlayer vortices induced by the Lorentz force in anisotropic high-Tc La_(1.87)Sr_(0.13)CuO_4 single crystals. It is found that 3 modes of flux motion switch depending on the transport current. By increasing the current a transition from the creep-like behavior of vortices to a steady flow of vortices was observed. Even higher current induced a continuous expansion of vortex-flow area indicating an inhomogeneous distribution of various pinning centers.



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