相关论文: Curie temperature of Sm$_2$Fe$_{17}$ and Nd$_2$Fe$…
We present a first-principles investigation of NdFe$_{12}$ and NdFe$_{12}$X (X = B, C, N, O, F) crystals with the ThMn$_{12}$ structure. Intersite magnetic couplings in these compounds, so-called exchange couplings, are estimated by…
We present a data set of calculated Curie temperatures for the main-phase compounds of rare-earth permanent magnets. We employ ab initio electronic structure calculations for the itinerant ferromagnetism and an effective spin model for the…
We present a first-principles study of RFe$_{12-x}$Cr$_{x}$ (R = Y, Nd, Sm) crystals with ThMn$_{12}$ structure. We discuss, within the mean field approximation, intersite magnetic couplings calculated using Liechtenstein's formula and…
We investigate the effects of various dopants (M = K--Br) on the Curie temperature of the magnetic compound NdFe12 through first-principles calculations. Analysis by the Korringa--Kohn--Rostoker method with the coherent potential…
Temperature-dependent magnetic properties of Nd$_2$Fe$_{14}$B permanent magnets, i.e., saturation magnetization $M_\text{s}(T)$, effective magnetic anisotropy constants $K_i^\text{eff}(T)$ ($i=1,2,3$), domain wall width $\delta_w(T)$, and…
We studied the temperature dependence of resistivity in a single crystalline Nd2Fe14B using a newly developed high temperature probe. This novel probe uses mechanical pin connectors instead of conducting glue/paste. From warming and cooling…
The generalized Heusler compounds Mn2CoZ (Z = Al, Ga, In, Si, Ge, Sn, Sb) with the Hg2CuTi structure are of large interest due to their half-metallic ferrimagnetism. The complex magnetic interactions between the constituents are studied by…
We study the dependence of magnetic interactions and Curie temperature in Ni(1+x)MnSb system on the Ni concentration within the framework of the density-functional theory. The calculation of the exchange parameters is based on the…
Gd6FeBi2 is reported as the only one room-temperature magnet with a Curie temperature (Tc) of ca. 350 K among more than hundreds of compounds with its structural type, which makes it more attractive in potential applications. To reveal the…
Intermetallic compounds R2Fe17 are perspective for applications as permanent magnets. Technologically these systems must have Curie temperature Tc much higher than room temperature and preferably have easy axis anisotropy. At the moment…
The interatomic exchange interactions and Curie temperatures in Ni-based full Heusler alloys Ni2MnX with X=Ga, In, Sn and Sb are studied within the framework of the density-functional theory. The calculation of the exchange parameters is…
Prediction of the Curie temperature is of significant importance for the design of ferromagnetic materials. Even though the Curie temperature has been estimated using the Heisenberg model, magnetic exchange coupling parameters widely used…
In this work we investigate Ising and classical Heisenberg models for two and three dimensional lattices in presence of diluted ferromagnetic dimers. For such models the Curie temperature as a function of ratio of intra-dimer exchange…
Double perovskites Sr$_2$FeMO$_6$ (M=Mo and Re) exhibit significant colossal magnetoresistance even at room temperature due to the high Curie Temperature (419K and 401K). However, such a high Curie Temperature is puzzling, given the large…
Ab initio calculations of formation energy and mixing energy for (Nd,R)2(Fe,Co)14B [R = rare-earth elements other than Nd] are presented to address the site preference of dopants and the corresponding magnetic properties. Contrasting trends…
The magnetic properties of the compound Fe$_5$Si$_{1-x}$P$_{x}$B$_2$ have been studied, with a focus on the Curie temperature $T_\textrm{C}$, saturation magnetization $M_\textrm{S}$, and magnetocrystalline anisotropy. Field and temperature…
We present a semi-analytic theory for the Curie temperature in diluted magnetic semi-conductors that treats disorder effects exactly in the effective Heisenberg Hamiltonian, and spin fluctuations within a local RPA. The exchange couplings…
The Heusler compounds Mn$_2$TiZ (Z = Al, Ga, In, Si, Ge, Sn, P, As, Sb) are of large interest due to their potential ferrimagnetic properties and high spin polarization. Here, we present calculations of the structural and magnetic…
We compare three first-principles methods of calculating the Curie temperature in two-dimensional (2D) ferromagnetic materials (FM), modeled using the Heisenberg model, and propose a simple formula for estimating the Curie temperature with…
We introduce the Hamiltonian to describe narrow band electrons. The physics of driving forces towards ferromagnetism is re-examined. Using different approximations it has been shown that the magnetic moments created by inter-site…