The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

V.v. Uryvaev - One of the best experts on this subject based on the ideXlab platform.

  • The cobalt Magnetic State in RCo3 intermetallics with light rare earth studied by thermal expansion
    Journal of Magnetism and Magnetic Materials, 2006
    Co-Authors: I.yu. Gaidukova, S.a. Granovsky, A.s. Markosyan, A.b. Petropavlovsky, V.e. Rodimin, V.v. Uryvaev
    Abstract:

    Abstract The temperature variation of the lattice parameters of RCo3 intermetallics with light R=Pr, Nd and Sm was studied by X-ray diffraction in the temperature range 10–550 K. From the magnitude of the magnetovolume effect arising below TC it has been concluded that in NdCo3 a temperature-induced change of the Co Magnetic State from a weak to a strong ferroMagnetic one occurs, whereas in PrCo3 and SmCo3 the Co sublattice remains in a weak Magnetic State down to at least 10 K. In SmCo3 an orthorhombic distortion of the rhombohedral crystal lattice was observed below 125 K. This is accounted for a spin reorientation of the spontaneous magnetization vector from the c-axis (high temperatures) toward the basal plane (low temperatures).

N. V. Baranov - One of the best experts on this subject based on the ideXlab platform.

  • Effect of rapid quenching on the Magnetic State, electrical resistivity and thermoMagnetic properties of Gd3Co
    Journal of Alloys and Compounds, 2015
    Co-Authors: D. A. Shishkin, A.v. Proshkin, N. V. Selezneva, E. G. Gerasimov, P.b. Terentev, A.m. Chirkova, K. Nenkov, Ludwig Schultz, N. V. Baranov
    Abstract:

    Abstract The ac-susceptibility, magnetization, electrical resistivity and specific heat measurements have been performed to study the changes in the Magnetic State and physical properties of the antiferroMagnetic Gd3Co compound after rapid quenching from the liquid melt. It has been observed that the amorphization of Gd3Co modifies the Magnetic State from antiferroMagnetic to a soft-ferroMagnetic like behavior, increases the Magnetic ordering temperature (by about 30%) and leads to substantial changes in the specific heat and electrical resistivity. A considerable enhancement of the exchange interactions in the rapidly solidified Gd3Co is ascribed to the appearance of a Magnetic moment on Co atoms up to 1.6 μB.

  • Impact of amorphization on the Magnetic State and magnetocaloric properties of Gd3Ni
    Applied Physics A, 2014
    Co-Authors: D. A. Shishkin, E. G. Gerasimov, P.b. Terentev, N. V. Baranov, A. F. Gubkin, A.s. Volegov, L. A. Stashkova
    Abstract:

    Rapid quenching and ball milling have been used to modify the Magnetic State and magnetocaloric properties of the intermetallic compound Gd3Ni. The melt-spun and ball-milled Gd3Ni samples are found to exhibit a soft ferroMagnetic-like behavior below 120 K, whereas in the crystalline State, the Gd3Ni compound is an antiferromagnet with a Neel temperature of about 99 K. The reduced value of the saturation magnetization observed in amorphous Gd3Ni samples is ascribed to the appearance of a Magnetic moment on Ni atoms. After amorphization, the Gd3Ni samples exhibit substantially improved magnetocaloric properties in a low field region in comparison with crystalline Gd3Ni.

  • A cluster-glass Magnetic State in R5Pd2 (R = Ho, Tb) compounds evidenced by AC-susceptibility and neutron scattering measurements.
    Journal of physics. Condensed matter : an Institute of Physics journal, 2013
    Co-Authors: A. F. Gubkin, E. A. Sherstobitova, P B Terentyev, Andreas Hoser, N. V. Baranov
    Abstract:

    AC- and DC-susceptibility, high-field magnetization and neutron diffraction measurements have been performed in order to study the Magnetic State of R5Pd2 (R = Ho, Tb) compounds. The results show that both compounds undergo cluster-glass freezing upon cooling below Tf. According to the neutron diffraction a long-range Magnetic order is absent down to 2 K and Magnetic clusters with short-range incommensurate antiferroMagnetic correlations exist not only below Tf but also in a wide temperature range above the freezing temperature (at least up to 2Tf). A complex cluster-glass Magnetic State existing in Ho5Pd2 and Tb5Pd2 down to low temperatures results in rather complicated magnetization behavior in DC and AC Magnetic fields. Such an unusual Magnetic State in compounds with a high rare-earth concentration may be associated with the layered type of their crystal structure and with substantial atomic disorder, which results in frustrations in the Magnetic subsystem.

  • Magnetic State of R1−xYxCo2 compounds near the critical concentration
    Journal of Alloys and Compounds, 1995
    Co-Authors: N. V. Baranov, A. N. Pirogov
    Abstract:

    Abstract The substitution of R ions in RCo2 compounds for non-Magnetic yttrium leads to the disappearance of the Magnetic moment in the itinerant d-electron subsystem at a critical Y concentration. The Magnetic State of the Ho1−xYxCo2 and Er1−xYxCo2 compounds near the corresponding critical concentrations xc=0.58 and xc=0.47 has been studied by means of neutron diffraction, electrical resistivity and a.c. susceptibility measurements. It is found that a long-range Magnetic order coexists with a short-range order in a narrow concentration range near xc (1 at.% for (Ho,Y)Co2). The change in Magnetic order with Y concentration in both systems occurs through a Magnetic phase transition of first order. The properties of the (Ho,Y)Co2 and (Er,Y)Co2 compounds near xc are strongly affected by the applied Magnetic field.

Igor A. Abrikosov - One of the best experts on this subject based on the ideXlab platform.

  • Influence of the Magnetic State on the Chemical Order-Disorder Transition Temperature in Fe-Ni Permalloy
    Physical review letters, 2010
    Co-Authors: Marcus Ekholm, Andrei V. Ruban, Helena Zapolsky, I.v. Vernyhora, D. Ledue, Igor A. Abrikosov
    Abstract:

    In Magnetic alloys, the effect of finite temperature Magnetic excitations on phase stability below the Curie temperature is poorly investigated, although many systems undergo phase transitions in this temperature range. We consider random Ni-rich Fe-Ni alloys, which undergo chemical order-disorder transition approximately 100 K below their Curie temperature, to demonstrate from ab initio calculations that deviations of the global Magnetic State from ideal ferroMagnetic order due to temperature induced magnetization reduction have a crucial effect on the chemical transition temperature. We propose a scheme where the Magnetic State is described by partially disordered local Magnetic moments, which in combination with Heisenberg Monte Carlo simulations of the magnetization allows us to reproduce the transition temperature in good agreement with experimental data.

  • Influence of global Magnetic State on chemical interactions in high-pressure high-temperature synthesis of B2 Fe2Si
    Applied Physics Letters, 2009
    Co-Authors: A. V. Ponomareva, Andrei Ruban, Natalia Dubrovinskaia, Leonid Dubrovinsky, Igor A. Abrikosov
    Abstract:

    We show that effective chemical interactions in an alloy can be tuned by its global Magnetic State, which opens exciting possibilities for materials synthesis. Using first-principles theory we demo ...

Susumu Okada - One of the best experts on this subject based on the ideXlab platform.

  • Phase control of Magnetic State of graphite thin films by electric field
    Applied Physics Letters, 2010
    Co-Authors: Minoru Otani, Yoshiteru Takagi, Mikito Koshino, Susumu Okada
    Abstract:

    Based on first-principle total-energy calculations, we have found that by applying an external electric field it is possible to control the Magnetic State of graphite thin film with the rhombohedral stacking arrangement. When exposed to a moderate electric field normal to the film, the surface of a thin film of rhombohedral graphite undergoes a Magnetic phase transition from the antiferroMagnetic State to the ferroMagnetic State. The polarized electron spin is primarily distributed in the bottommost layer of the film, which forms the interface with the negative electrode. The amount of polarized electron spin is calculated to be 0.067 μB/nm2. The ferroMagnetic ordering with the characteristic distribution of the polarized electron spin opens the possibility of using graphite thin films in electronic devices with spin degree of freedom.

Simon J. Clarke - One of the best experts on this subject based on the ideXlab platform.

  • Enhanced superfluid stiffness, lowered superconducting transition temperature, and field-induced Magnetic State of the pnictide superconductor LiFeAs
    Physical Review B, 2009
    Co-Authors: Francis L. Pratt, Peter J. Baker, Stephen J. Blundell, Tom Lancaster, H. J. Lewtas, Paul Adamson, Michael J. Pitcher, D. R. Parker, Simon J. Clarke
    Abstract:

    Transverse-field muon-spin rotation measurements performed on two samples of LiFeAs demonstrate that the superfluid stiffness of the superconducting condensate in relation to its superconducting transition temperature is enhanced compared to other pnictide superconductors. Evidence is seen for a field-induced Magnetic State in a sample with a significantly suppressed superconducting transition temperature. The results in this system highlight the role of direct Fe-Fe interactions in frustrating pairing mediated by antiferroMagnetic fluctuations and indicate that, in common with other pnictide superconductors, the system is close to a Magnetic instability.