Karkin A E, Wolf T, Goshchitskii B N
Institute of Metal Physics UB RAS, 620219 Ekaterinburg, Russia.
J Phys Condens Matter. 2014 Jul 9;26(27):275702. doi: 10.1088/0953-8984/26/27/275702. Epub 2014 Jun 17.
Resistivity ρ(T), Hall coefficient RH(T), superconducting transition temperature Tc and slopes of the upper critical field dHc2/dT were studied in (Ba1-xKx)Fe2As2 (x = 0.218, 0.356, 0.531) single crystals irradiated with fast neutrons. It is found that dTc/dρSC-the rate of decreasing Tc as a function of the ρSC (ρSC is the resistivity at T = Tc)-linearly increases with concentration x. Slow changes in the Hall coefficient RH, as well as the quadratic electronic contribution to the resistivity, show that there are no substantial changes in the topology of the Fermi surface caused by irradiation. The slopes of the upper critical field dHc2/dT in ab and c directions as a function of ρSC determined by Hall measurements show a reasonable agreement with a model that suggests constancy of the band parameters.
研究了快中子辐照的（Ba1-xKx）Fe2As2（x = 0.218、0.356、0.531）单晶中的电阻率ρ(T)、霍尔系数RH(T)、超导转变温度Tc以及上临界场斜率dHc2/dT。发现dTc/dρSC——即Tc随ρSC（ρSC是T = Tc时的电阻率）的降低速率——随浓度x线性增加。霍尔系数RH的缓慢变化以及电阻率的二次电子贡献表明，辐照并未导致费米面拓扑结构发生实质性变化。通过霍尔测量确定的ab和c方向上作为ρSC函数的上临界场斜率dHc2/dT与表明能带参数恒定的模型显示出合理的一致性。
