The field dependence of magnetization at T = 4.2 K and in magnetic fields of up to 70 kOe, temperature dependences of magnetization (2 K < T < 300 K), heat capacity (2 K < T < 30 K) and magnetic susceptibility (2 K < T < 1000 K) for Mn_1.99Co_0.96Al_1.05 and Mn_1.79Co_1.25Al_0.96 alloys, closed in composition to the Mn₂CoAl spin gapless semiconductor, were studied. Alloys studied were demonstrated to be the band ferromagnets. Their high-field (H > 11 kOe) magnetization is described in the Stoner models with the Rhodes-Wohlfarth parameter p_RW = 1.3 for Mn_1.99Co_0.96Al_1.05 and p_RW = 2.3 for Mn_1.79Co_1.25Al_0.96. When the composition deviates from the stoichiometric Mn₂CoAl, the spontaneous moment decreases slightly, the effective moment, on the contrary, increases. In this case, a negative sign of the temperature-independent component of the paramagnetic susceptibility is observed. The density of states n(E_F) at Fermi level and the Debye temperature Θ_D of studied alloys have the usual values for 3d-metal alloys.

中文翻译：

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合金的磁性和热学性质与自旋无间隙半导体Mn2CoAl接近

在T  = 4.2 K和最高70 kOe的磁场中，磁化强度的磁场依赖性，磁化强度的温度依赖性（2 K <  T  <300 K），热容（2 K <  T  <30 K）和磁化率（2研究 了Mn _1.99 Co _0.96 Al _1.05和Mn _1.79 Co _1.25 Al _0.96合金的K < T <1000 K），它们在组成上与Mn ₂ CoAl自旋无间隙半导体接近。所研究的合金被证明是带状铁磁体。他们的高场（H > 11千奥斯特）磁化强度在斯通模型与所描述的罗德-Wohlfarth参数p _RW  = 1.3锰_1.99钴_0.96铝_1.05和p _RW  = 2.3锰_1.79钴_1.25铝_0.96。当组成偏离化学计量的Mn ₂ CoAl时，自发力矩会略有下降，相反，有效力矩会增加。在这种情况下，观察到顺磁敏感性的温度无关分量的负号。态密度Ñ（E _˚F）在费米能级和德拜温度Θ _d所研究的合金中的3d合金具有通常的值。