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Measuring the Penetration Depth Anisotropy in MgB$_2$ using Small-Angle Neutron Scattering

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 نشر من قبل Dilip Pal
 تاريخ النشر 2005
  مجال البحث فيزياء
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Using small-angle neutron scattering we have measured the misalignment between an applied field of 4 kOe and the flux-line lattice in MgB$_2$, as the field is rotated away from the c axis by an angle $theta$. The measurements, performed at 4.9 K, showed the vortices canting towards the c axis for all field orientations. Using a two-band/two-gap model to calculate the magnetization we are able to fit our results yielding a penetration depth anisotropy, $glam = 1.1 pm 0.1$.



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