块体金属玻璃Zr46.75Ti8.25Cu7.5Ni10Be27.5的超导与负电阻温度系数

测量了块体金属玻璃Zr_46.75Ti_8.25Cu_7.5Ni₁₀Be_27.5在退火前后其电阻值随温度的变化,测量的温度范围为1.5—300K.样品在退火前后都发现有超导现象.零磁场下其超导转变温度T_c分别为1.84和3.76K.在5—300K温度范围内,原始样品具有负的电阻温度系数.如果取Zr, Ti, Cu, Ni及Be分别贡献出1.5, 1.5, 0.5, 0.5及两个传导 关键词： 块体金属玻璃 超导 电阻温度系数

Superconductivity and negative temperature coefficient of the resistivity of bulk metallic glass Zr46.75Ti8.25Cu7.5Ni10Be27.5

Electrical-resistivity measurements between 1.5 K and 300 K were performed on the Zr_46.75Ti_8.25Cu_7.5Ni₁₀Be_27.5 bulk metallic glasses (BMGs) before and after annealing. Results of the superconducting transition temperature measurements are presented for the BMG Zr_46.75Ti_8.25Cu_7.5Ni₁₀Be_27.5. The superconducting critical temperature T_c is 1.84K for the as-prepared metallic glassy sample and 3.76K for the annealed sample at zero magnetic fields. The as-prepared metallic glassy sample exhibits negative temperature coefficient of the resistivity in the temperature range from 5 to 300 K. The negative temperature coefficient of the resistivity of the as-prepared metallic glassy sample can be reasonably understood with the extended Faber-Ziman theory in terms of the diffraction model for metallic glasses if it is assumed that Zr, Ti, Cu, Ni and Be contribute 1.5, 1.5, 0.5, 0.5 and 2 conduction electrons, respectively. The R(T) of the BMG Zr_46.75Ti_8.25Cu_7.5Ni₁₀Be_27.5 over the temperature range from 5 to 300 K was analyzed by fitting it to a polynomial using a least-squares procedure.