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arXiv · 0806.0515

Enhanced superconductivity in Hf-base metallic glasses

Emil Tafra·Mario Basletic·Ramir Ristic·Emil Babic·Amir Hamzic
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Abstract

Systematic study of electrical resistivity of Hf_{100-x}Fe_x (x=20,25), Hf_{100-x}Cu_x (x=30,40,50), and Ti_{65}Cu_{35} metallic glasses has been done in the temperature range 0.3 K - 290 K, and in magnetic fields B <= 5 T. All Hf-base alloys are superconducting with T_c >= 0.44 K, which is well above T_c of pure crystalline Hf (0.13 K). From the initial slopes of the upper critical fields, (dH_{c2}/dT)_{T_c}, and resistivities we determined the dressed electronic densities of states, N_γ(E_F), for all alloys. Both T_c and N_γ(E_F) decrease with increasing x (Fe and Cu content). The results are compared with those for corresponding Zr-base metallic glasses and ion-implanted Hf films.

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Emil Tafra, Mario Basletic, Ramir Ristic, Emil Babic, Amir Hamzic. 2008-09-26. Enhanced superconductivity in Hf-base metallic glasses. https://doi.org/10.1088/0953-8984%2F20%2F42%2F425215

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