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arXiv · 0809.4274

Effect of Pt doping on the critical temperature and upper critical field in YNi2-xPtxB2C (x=0-0.2)

Sourin Mukhopadhyay·Goutam Sheet·A. K. Nigam·Pratap Raychaudhuri·H. Takeya
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Abstract

We investigate the evolution of superconducting properties by doping non-magnetic impurity in single crystals of YNi2-xPtxB2C (x=0-0.2). With increasing Pt doping the critical temperature (Tc) monotonically decreases from 15.85K and saturates to a value ~13K for x>0.14. However, unlike conventional s-wave superconductors, the upper critical field (HC2) along both crystallographic directions a and c decreases with increasing Pt doping. Specific heat measurements show that the density of states (N(EF)) at the Fermi level (EF) and the Debye temperatures (Theta_D) in this series remains constant within the error bars of our measurement. We explain our results based on the increase in intraband scattering in the multiband superconductor YNi2B2C.

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Sourin Mukhopadhyay, Goutam Sheet, A. K. Nigam, Pratap Raychaudhuri, H. Takeya. 2008-09-24. Effect of Pt doping on the critical temperature and upper critical field in YNi2-xPtxB2C (x=0-0.2). https://doi.org/10.1103/physrevb.79.132505

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