论文标题
Zrzn $ _2 $的电子相关，光谱和磁性
Electronic correlations, spectral and magnetic properties of ZrZn$_2$
论文作者
论文摘要
我们介绍了一项原型弱铁磁Zrzn $ _2 $的理论研究结果。我们使用密度功能理论（DFT）+动态平均场理论（DMFT）方法来研究电子和局部磁性。所获得的DFT+DMFT电子自我能力是Fermi-Liquid，表明Zr $ 4D $状态的有效质量较小，$ M^*/M \ sim 1.1-1.1-1.3 $伴随着$ T_ {2G} $ Symmetry的电子状态中部分形成的本地瞬间。电子相互作用的效果被证明对于确定某些费米表面片的正确拓扑至关重要。为了详细研究Curie温度$ t _ {\ rm C} $的压力依赖性和相应的压力诱导的量子相变，我们考虑了一种有效的单波段模型，该模型使用ZR $ 4D $对状态总密度的贡献构建。在静态和动态的平均场理论以及自旋特性方法中研究了该模型。我们表明，自旋特性方法在环境压力和压力依赖性$ t _ {\ rm c}（p）$中产生易感性的温度依赖性，包括$ p \ p \ gpa的一阶量子相变，与实验数据相当。
We present results of a theoretical study of a prototypical weak ferromagnet ZrZn$_2$. We use the density-functional theory (DFT)+dynamical mean-field theory (DMFT) method to study the electronic and local magnetic properties. The obtained DFT+DMFT electronic self-energies are Fermi-liquid like, indicating a small effective mass enhancement of the Zr $4d$ states $m^*/m\sim 1.1 - 1.3$ accompanied by partly formed local moments within the electronic states of $t_{2g}$ symmetry. The effect of electronic interaction is shown to be essential for determining the correct topology of some of the Fermi surface sheets. To study in detail the pressure dependence of the Curie temperature $T_{\rm C}$ and corresponding pressure-induced quantum phase transition, we consider an effective single-band model, constructed using the Zr $4d$ contribution to the total density of states. The model is studied within static and dynamic mean-field theory, as well as spin-fermion approach. We show that the spin-fermion approach yields the temperature dependence of susceptibility at ambient pressure and the pressure dependence $T_{\rm C}(p)$, including the first-order quantum phase transition at $p\approx 1.7$~GPa, comparable well with the experimental data.
