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Anisotropic superconductivity in layered LaSb$_2$: the role of phase fluctuations

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 نشر من قبل John DiTusa
 تاريخ النشر 2010
  مجال البحث فيزياء
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We present magnetic susceptibility and electrical transport measurements of the highly anisotropic compound LaSb$_2$ observing a very broad transition into a clean, consistent with type-I, superconducting state with distinct features of 2 dimensionality. Application of hydrostatic pressure induces a 2- to 3-dimensional crossover evidenced by a reduced anisotropy and transition width. The superconducting transition appears phase fluctuation limited at ambient pressure with fluctuations observed for temperatures greater than 8 times the superconducting critical temperature.



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