In this work, we investigate models for bulk, bi-, and multilayers containing half-metallic ferromagnets (HMFs), at zero and at finite temperature, in order to elucidate the effects of strong electronic correlations on the spectral properties (density of states). Our focus is on the evolution of the finite-temperature many-body induced tails in the half-metallic gap. To this end, the dynamical mean-field theory (DMFT) is employed. For the bulk, a Bethe lattice model is solved using a matrix product states based impurity solver at zero temperature and a continuous-time quantum Monte Carlo (CT-QMC) solver at finite temperature. We demonstrate numerically, in agreement with the analytical result, that the tails vanish at the Fermi level at zero temperature. In order to study multilayers, taken to be square lattices within the layers, we use the real-space DMFT extension with the CT-QMC impurity solver. For bilayers formed by the HMF with a band or correlated insulator, we find that charge fluctuations between the layers enhance the finite-temperature tails. In addition, in the presence of interlayer hopping, a coherent quasiparticle peak forms in the otherwise correlated insulator. In the multilayer heterostructure setup, we find that by suitably choosing the model parameters, the tails at the HMF-Mott insulator interface can be reduced significantly and that a high spin polarization is conceivable, even in the presence of long-ranged electrostatic interactions.

中文翻译：

---

存在局部多体相关性的含半金属铁磁体异质结构的光谱性质

在这项工作中，我们研究了在零温度和有限温度下包含半金属铁磁体（HMF）的块状，双层和多层模型，以阐明强电子相关性对光谱特性（态密度）的影响。我们的重点是在半金属间隙中有限温度多体感应尾巴的演化。为此，采用了动态平均场理论（DMFT）。对于大部分，使用零温度下基于矩阵乘积状态的杂质求解器和有限温度下的连续时间量子蒙特卡洛（CT-QMC）求解器求解Bethe晶格模型。与分析结果一致，我们通过数值证明了在零温度下尾巴在费米能级上消失。为了研究多层（被视为层内的方格），我们将实空间DMFT扩展与CT-QMC杂质求解器配合使用。对于由HMF与带或相关绝缘体形成的双层，我们发现层之间的电荷波动会增强有限温度的尾部。另外，在存在层间跳变的情况下，在否则相关的绝缘体中形成相干的准粒子峰。在多层异质结构设置中，我们发现，通过适当地选择的模型参数，在HMF-莫特绝缘体界面尾部可以显著和高自旋极化想到，即使在长程静电相互作用的存在而降低。另外，在存在层间跳变的情况下，在否则相关的绝缘体中形成相干的准粒子峰。在多层异质结构设置中，我们发现，通过适当地选择的模型参数，在HMF-莫特绝缘体界面尾部可以显著和高自旋极化想到，即使在长程静电相互作用的存在而降低。另外，在存在层间跳变的情况下，在否则相关的绝缘体中形成相干的准粒子峰。在多层异质结构设置中，我们发现，通过适当地选择的模型参数，在HMF-莫特绝缘体界面尾部可以显著和高自旋极化想到，即使在长程静电相互作用的存在而降低。