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Doping effect on the evolution of the pairing symmetry in n-type superconductor near antiferromagnetic phase boundary

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 نشر من قبل Denis Petukhov
 تاريخ النشر 2014
  مجال البحث فيزياء
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We present the investigation results of the in-plane {rho}(T) resistivity tensor at the temperature range 0.4-40 K in magnetic fields up to 90kOe (H||c, J||ab) for electron-doped Nd{2-x}Ce{x}CuO{4+{delta}} with different degree of disorder near antiferromagnetic - superconducting phase boundary. We have experimentally found that for optimally doped compound both the upper critical field slope and the critical temperature decrease with increasing of the disorder parameter (d-wave pairing) while in the case of the underdoped system the critical temperature remains constant and (dHc2/dT)|Tc increases with increasing of the disorder (s-wave pairing). These features suggest a possible implementation of the complex mixture state as the (s+id)-pairing.

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