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Superconducting Properties of Atomic-Disordered Compound MgCNi_3

A. Karkin·B. Goshchitskii·E. Kurmaev·Z. A. Ren·G. C. Che
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Abstract

The effect of radiation-induced disordering in a nuclear reactor (fast neutrons fluence Φ= 5\cdot10^{19} cm^2, T_{\text{irr}} = 340 K) on resistivity ρ, superconducting transition temperature T_C and upper critical field H_{C_2} of polycrystalline MgCNi_3 samples was investigated. It was found that T_C decreases under irradiation from 6.5 to 2.9 K and completely recovers after annealing at 600 ^\circC. Temperature dependences ρ(T) are characteristic of compounds with strong electron-phonon interaction. The dH_{C_2}/dT behaviour testifies to a considerable decrease in density of electronic state at Fermi level N(E_F) in the course of disordering.

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A. Karkin, B. Goshchitskii, E. Kurmaev, Z. A. Ren, G. C. Che. 2002-09-25. Superconducting Properties of Atomic-Disordered Compound MgCNi_3. https://arxiv.org/abs/cond-mat/0209575

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