相关论文: Covalency effects on the magnetism of EuRh2P2
Unusual phases and phase transitions are seen at the magnetic-nonmagnetic boundary in Ce, Eu and Yb-based compounds. EuNi$_2$P$_{2}$ is a very unusual valence fluctuating Eu system, because at low temperatures the Eu valence stays close to…
We report on the crystal structure, physical properties, and electronic structure calculations for the ternary pnictide compound EuCr2As2. X-ray diffraction studies confirmed that EuCr2As2 crystalizes in the ThCr2Si2-type tetragonal…
We present a detailed study of the temperature evolution of the crystal structure, specific heat, magnetic susceptibility and resistivity of single crystals of the paradigmatic valence-fluctuating compound EuIr$_2$Si$_2$. A comparison to…
The interaction between localized f and itinerant conduction electrons is crucial in the electronic properties of heavy fermion and valence fluctuating compounds. Using high-resolution angle-resolved photoemission spectroscopy, we…
We report $^{31}$P NMR measurements under various magnetic fields up to 7 T for the intermediate valence compound EuNi$_2$P$_2$, which shows heavy electronic states at low temperatures. In the high-temperature region above 40 K, the Knight…
Valence transitions in strongly correlated electron systems are caused by orbital hybridization and Coulomb interactions between localized and delocalized electrons. The transition can be triggered by changes in the electronic structure and…
Ternary iron phosphide EuFe$_2$P$_2$ with ThCr$_2$Si$_2$-type structure has been systematically studied by the measurements of crystal structure, magnetization, M\"{o}ssbauer effect, transport properties and specific heat. The structural…
The solid solution 122 compounds, Eu(Co$_{1-x}$Ni$_{x}$)$_{2}$P$_{2}$, show valence transition between divalent state and intermediate valence states at Eu, which is firmly correlated to multiple degrees of freedom in the solid such as the…
We present results of hard X-ray angle-resolved photoemission spectroscopy and photoemission diffraction measurements performed on high-quality single crystals of the valence transition compound EuPd$_2$Si$_2$ for temperatures 25~K $\leq$ T…
We study the mixed valence transition ($T$$_{v}$ $\sim$80 K) in EuNi$_{2}$(Si$_{0.2}$Ge$_{0.8}$)$_{2}$ using Eu 3$d-4f$ X-ray absorption spectroscopy (XAS) and resonant photoemission spectroscopy (RESPES). The Eu$^{2+}$ and Eu$^{3+}$ main…
In divalent Eu systems, the 4f local moment has a pure spin state J=S=7/2. Although the absence of orbital moment precludes crystal electric field effects, we report a sizeable magnetic anisotropy in single crystals of EuRh2Si2. We observed…
We report a comprehensive high-pressure study on the antiferromagnetic topological insulator EuSn2As2 up to 21.1 GPa through measurements of synchrotron x-ray diffraction, electrical resistance, magnetic resistance, and Hall transports…
EuC$_2$ is a ferromagnet with a Curie-temperature of $T_C \simeq 15\,$K. It is semiconducting with the particularity that the resistivity drops by about 5 orders of magnitude on cooling through $T_C$, which is therefore called a…
The metallic compound EuCo2P2 with the body-centered tetragonal ThCr2Si2 structure containing Eu spins 7/2 was previously shown from single-crystal neutron diffraction measurements to exhibit a helical antiferromagnetic (AFM) structure…
EuRhAl4Si2, crystallizes in tetragonal crystal structure and orders antiferromagnetically at ~12 K. The isothermal magnetization along the two principle directions is highly anisotropic despite Eu2+ being an S-state ion. The variation of…
The Eu-based compound, EuCu2As2, crystallizing in the ThCr2Si2-type tetragonal structure, has been synthesized and its magnetic behavior has been investigated by magnetization (M), heat-capacity (C) and electrical resistivity (rho)…
We report on the successful single crystal growth of pure EuRh${_2}$Si${_2}$ and of Eu(Rh$_{1-x}$Co$_{x}$)$_2$Si$_2$ with $x\leq0.23$ by the flux method. Through Co substitution, EuRh$_2$Si$_2$ can be tuned from stable antiferromagnetism…
The compound EuPd2Si2 is a well-known valence-fluctuating compound with a largest variation of Eu valence in a narrow temperature interval (around 150 K). The ball-milled form of this compound was investigated to understand the Eu valence…
Using a density functional method with explicit account for strong Coulomb repulsion within the 4f shell, we calculate effective exchange parameters and the corresponding ordering temperatures of the (ferro)magnetic insulating Eu…
Electrical resistivity \rho(T) of the 5f ferromagnet UGa2 was investigated for single-crystal samples as a function of pressure and magnetic field. The Curie temperature monotonously increases from T$_{C}$ = 124 K under quasi-hydrostatic…