AI 中文总结
研究 Fe 亚晶格上有替代无序的 B2 有序合金磁性能，通过第一性原理计算，发现 d 带填充是磁稳定性主要参数，Mn 取代致自旋极化崩溃，Co 取代起“磁硬化”作用，为控制磁稳定性提供微观框架。
AI 中文摘要
利用相干势近似下的第一性原理计算，研究了 Fe 亚晶格上具有替代无序的 B2 有序\zfr~合金的成分依赖磁性能。通过在 Fe 亚晶格上系统地取代 Mn 和 Co，确定了 d 带填充是控制该巡游体系磁稳定性的主要参数。Mn 取代（空穴掺杂）使费米能级移入少数自旋键合态，导致自旋极化崩溃并出现竞争反铁磁相互作用。Co 取代（电子掺杂）则通过将费米能级固定在多数自旋赝能隙内起到“磁硬化剂”作用。这些结果表明，相对于赝能隙调节费米能级为控制 B2 有序巡游磁体中的磁稳定性提供了一个系统的微观框架。
英文摘要
The composition-dependent magnetic properties of B2-ordered \zfr~alloys with substitutional disorder on the Fe sublattice are investigated using first-principles calculations within the coherent potential approximation. By systematically substituting Mn and Co on the Fe sublattice, we establish $d$-band filling as the primary control parameter governing magnetic stability in this itinerant system. Mn substitution (hole doping) shifts the Fermi level into the minority-spin bonding states, driving a collapse of spin polarization (crossing zero at $x \approx 0.5$) and the emergence of competing antiferromagnetic interactions ($η_\mathrm{Mn} < 0$). Even though the ferromagnetic configuration remains energetically well separated from the G-type AFM-II configuration across the studied range ($ΔE$ up to $\sim$0.35~eV/atom), this exchange competition drives an ``itinerant magnetic softness'' that suppresses the Curie temperature by $\sim$450~K -- a finite-temperature instability set by the near-cancellation of competing exchange interactions rather than by AFM--FM energy proximity. In contrast, Co substitution (electron doping) acts as a ``magnetic hardener'' by pinning the Fermi level within the majority-spin pseudogap, preserving high spin polarization ($|P| \approx 0.75$) and stabilizing ferromagnetic exchange across the full composition range. These results show that tuning the Fermi level relative to the pseudogap provides a systematic, microscopic framework for controlling magnetic stability in B2-ordered itinerant magnets, distinct from simple magneto-volume models.
