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Magnetic susceptibility and superconductivity of TE-TL metallic glasses: influence of electronic structure

TE‐TL (TE=Ti, Zr, Hf and TL=Ni, Cu) alloys show wide glass‐forming ranges which enables detailed study of the change in the electronic structure and properties on alloying and, thus a thorough comparison between the model and experimental data. Amorphous TETL alloys have been extensively studied in recent decades and interest in these alloys further increased after the discovery of TE‐TL based bulk metallic glasses (BMGs). In amorphous TE‐TL alloys the properties that are directly related to the electronic density of states (DOS) often show linear variations with TL content. The effect of alloying with TL can be approximated by the dilution of amorphous TE. Thus , one can extrapolate the data for glassy TE‐TL alloys to zero TL content in order to deduce the properties of amorphous TE (also in Cu‐TE alloys we extrapolate data to zero TE to deduce the properties of amorphous Cu). The magnetic susceptibility was measured with a SQUID magnetometer MPMS in a magnetic field B<5.5T or with Faraday method. Superconductivity transition temperature was obtained from resistivity measurements. We explained magnetic susceptibility by adding Pauli susceptibility χp, the temperatureindependent ionic core diamagnetism χion and the orbital paramagnetism χorb. The Pauli paramagnetism of the d‐band χp is enhanced over the free‐electron value, χp0, due to exchange interaction, χp=S χp0, where S is the Stoner enhancement factor. χp is only weakly dependent on temperature. We use the specific heat and superconducting transition temperature data (ours and from literature) to determine the electron density of states (bare and “dressed”), corresponding free‐electron value for the Pauli paramagnetism χp0, and the Stoner enhancement factor S. All observed and derived parameters depend sensitively on selected TE.

Magnetic susceptibility; superconductivity

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