相关论文: Phase diagram and isotope effect in (PrEu)_0.7Ca_0…

The unconventional electronic ground state of Sr$_3$IrRuO$_7$ is explored via resonant x-ray scattering techniques and angle-resolved photoemission measurements. As the Ru content approaches $x=0.5$ in Sr$_3$(Ir$_{1-x}$Ru$_x$)$_2$O$_7$,…

Pressure effects on the charge and spin states and the relation between the ferromagnetic and metallic states were explored on the small bandwidth manganite Pr$_{1-x}$Ca$_{x}$MnO$_{3}$ (x = 0.25, 0.3, 0.35). Under pressure, the charge…

The magnetic and magnetotransport properties of the oxygen deficient perovskites, SrCo1-xMxO3-d with M = Nb and Ru, were investigated. Both Nb- and Ru-substituted cobaltites are weak ferromagnets, with transition temperatures Tm of 130-150…

In the commented Letter Vogt et al. (Phys.Rev.Lett. 84 (2000) 2969) claim the existence of a spin-state transition in YBaCo2O5. We think that this claim about the change from the low spin to high spin state upon cooling in YBaCo2O5 is…

We report 51V-NMR study on a high-quality powder sample of volborthite Cu3V2O7(OH)2/2H2O, a spin-1/2 Heisenberg antiferromagnet on a distorted kagome lattice formed by isosceles triangles. In the magnetic fields below 4.5 T, a sharp peak in…

We have investigated the dielectric and magnetic properties of Eu$_{0.595}$Y$_{0.405}$MnO$_{3}$ $without$ the presence of the 4$f$ magnetic moments of the rare earth ions, and have found two ferroelectric phases with polarization along the…

The effects of hydrostatic pressure on the static magnetism in Eu(Fe$_{0.925}$Co$_{0.075}$)$_{2}$As$_{2}$ are investigated by complementary electrical resistivity, ac magnetic susceptibility and single-crystal neutron diffraction…

The identification of quantum spin liquid phases in Kitaev candidate materials remains a major experimental challenge. Since most Kitaev candidates develop antiferromagnetic (AFM) order at low temperatures, currently there are great…

Ca_3Co_{2-x}Mn_xO_6 (x ~ 0.96) is a multiferroic with spin-chains of alternating Co(2+) and Mn(4+) ions. The spin state of Co(2+) remains unresolved, due to a discrepancy between high temperature X-ray absorption (S=3/2) and low temperature…

We have investigated the magnetic properties and mapped out the phase diagram of the honeycomb magnet Na2Co2TeO6 with Co 3d7 in out-of-plane magnetic fields. This material has previously been proposed to show nearest-neighbor Kitaev…

The interplay of crystal electric field, temperature, and spin-orbit coupling can yield a Kramers ion and thus an effective S = 1/2 ground state for Co2+ ions (3d7), which is often the case for low dimensional materials. This is because a…

Magnetic state is a partial ordered state if only part of the electrons in the system give contribution to the magnetic order. We study Heisenberg model of two sublattice spin system, on the body-centered cubic lattice, with…

Precise thermal expansion and magnetostriction studies of the intermetallic compound Eu$_2$CuSi$_3$ in the temperature range between 5 and 300 K are presented. A clear sign of magnetic second order phase transition at the ferromagnetic…

Using the dynamical mean-field approximation we investigate formation of excitonic condensate in the two-band Hubbard model in the vicinity of the spin-state transition. With temperature and band filling as the control parameters we realize…

In this study we examine the phase transitions in single crystals of [(CH3)2NH2]Co(HCOO)3], using magnetization and specific heat measurements as a function of temperature and magnetic field. Magnetisation measurements indicate a transition…

We show for the system La1-xCexCoO3 (0.1 <= x <= 0.4) that it is possible to synthesize electron-doped cobaltites by the growth of epitaxial thin films. For La1-xCexCoO3, ferromagnetic order is observed within the entire doping range (with…

Electron-doped Eu(Fe$_{0.93}$Rh$_{0.07}$)$_2$As$_2$ has been systematically studied by high pressure investigations of the magnetic and electrical transport properties, in order to unravel the complex interplay of superconductivity and…

We explore quantum-thermodynamic effects in a phosphorous (P)-doped graphene monolayer subjected to biaxial tensile strain. Introducing substitutional P atoms in the graphene lattice generates a tunable spin magnetic moment controlled by…

The delicate balance between spin-orbit coupling, Coulomb repulsion and crystalline electric field interactions observed in Ir-based oxides is usually manifested as exotic magnetic behavior. Here we investigate the evolution of the exchange…

Using soft-x-ray absorption spectroscopy at the Co-$L_{2,3}$ and O-$K$ edges, we demonstrate that the Co$^{3+}$ ions with the CoO$_{5}$ pyramidal coordination in the layered Sr$_2$CoO$_3$Cl compound are unambiguously in the high spin state.…