由无序诱导能带展宽控制的稀 Cu-3d 合金中的电阻率
Resistivity in Dilute Cu-3d Alloys Governed by Disorder-Induced Band Broadening
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中文总结 AI 辅助
研究室温下稀 Cu-3d 合金电阻率控制机制，用第一性原理计算，在无序局域矩框架内描述顺磁态，发现电阻率与费米面处布洛赫谱函数半高宽强相关，由无序诱导能带展宽控制，为 Cu 基合金中林德规则失效提供微观解释。
中文摘要 AI 辅助
本文利用基于 Korringa-Kohn-Rostoker 相干势近似并结合 Kubo-Greenwood 形式的第一性原理计算，研究了室温下稀 Cu-3d 过渡金属合金中电阻率的控制机制，该机制与大多数实际应用相关且不同于早期理论工作所涉及的低温近藤屏蔽机制。顺磁态在无序局域矩（DLM）框架内描述，对应局域矩顺磁体而非泡利顺磁体。研究表明，仅在 DLM 描述中能重现实验观测到的电阻率趋势，非磁性和铁磁态无法捕捉正确的元素依赖性。与基于费米能级态密度的传统解释相反，电阻率与费米面处布洛赫谱函数（BSF）的半高宽（FWHM）有强相关性，反映了无序诱导的电子态寿命展宽，直接与控制电阻率的散射率相关。不同磁态下确定了电阻率和 BSF 展宽之间的通用幂律标度。这些结果表明，电阻率由动量空间中无序诱导的能带展宽而非局域态密度效应控制，为 Cu 基合金中林德规则的失效提供了统一的微观解释。
英文摘要
The mechanism governing the resistivity in dilute Cu-3d transition-metal alloys at ambient temperature -- the regime relevant to most practical applications and distinct from the low-temperature, Kondo-screened regime addressed by earlier theoretical work -- is investigated using first-principles calculations based on the Korringa--Kohn--Rostoker coherent potential approximation combined with the Kubo--Greenwood formalism. The paramagnetic state is described within the disordered local moment (DLM) framework, corresponding to a local-moment paramagnet rather than a Pauli paramagnet. We show that the experimentally observed resistivity trends are reproduced only within the DLM description, while nonmagnetic and ferromagnetic states fail to capture the correct element dependence. Contrary to conventional interpretations based on the density of states at the Fermi level, the resistivity exhibits a strong correlation with the full width at half maximum (FWHM) of the Bloch spectral function (BSF) on the Fermi surface. This correlation reflects the disorder-induced lifetime broadening of electronic states, directly related to the scattering rate that governs electrical resistivity. A common power-law scaling between resistivity and BSF broadening is identified across different magnetic states. These results demonstrate that the resistivity is governed by disorder-induced band broadening in momentum space rather than by local density-of-states effects, providing a unified microscopic interpretation of the breakdown of Linde's rule in Cu-based alloys.
