Mao Qianhui, Wang Hangdong, Yang Jinhu, Liu HanLei, Pan Mengyang, Li Ruixue, Hao Haoshan, Fang Minghu
College of Science, Henan University of Engineering, Zhengzhou 451191, People's Republic of China. Henan Key Laboratory of Electronic Ceramic Materials and Applications, Henan University of Engineering, Zhengzhou 451191, People's Republic of China.
J Phys Condens Matter. 2020 Jan 23;32(4):045801. doi: 10.1088/1361-648X/ab4b6a. Epub 2019 Oct 7.
We have investigated the magnetism and magnetocaloric effect of TlCo Ni S (0 [Formula: see text] x [Formula: see text] 0.05). TlCoS and TlCoNiS are ferromagnetically ordered below 153 K and 142 K with saturated moment 0.82 [Formula: see text] [Formula: see text]/Co and 0.80 [Formula: see text] [Formula: see text]/Co, respectively, while TlCoNiS shows ferromagnetic transition at 132 K. The magnetism displays slightly itinerant character, as inferred from the Rhodes-Wohlfarth ratio. An unusual historical dependence of magnetization in TlCoNiS is consistently observed by scanning both the temperature and magnetic field. The isothermal magnetic entropy change ([Formula: see text] S [Formula: see text]) of TlCoS and TlCoNiS are calculated by Maxwell relation and a temperature averaged entropy change is adopted to estimate the figure of merit for the compounds.
我们研究了TlCoNiₓS（0≤x≤0.05）的磁性和磁热效应。TlCoS和TlCoNiS在153K和142K以下呈铁磁有序，饱和磁矩分别为0.82μ₀B/Co和0.80μ₀B/Co，而TlCoNiS在132K时出现铁磁转变。从罗兹-沃尔法思比率推断，磁性表现出轻微的巡游特性。通过扫描温度和磁场，始终观察到TlCoNiS中磁化强度存在不寻常的历史依赖性。通过麦克斯韦关系计算了TlCoS和TlCoNiS的等温磁熵变（ΔSₘ），并采用温度平均熵变来估计这些化合物的品质因数。
