Search results for "Magnetism"

NMR study of magnetic order, metamagnetic transitions, and low-temperature spin freezing in Ca3Co2O6

2011

We report on a (59)Co NMR investigation of the trigonal cobaltate Ca(3)Co(2)O(6) carried out on a single crystal, providing precise determinations of the electric field gradient and chemical shift tensors, and of the internal magnetic fields at the nonmagnetic Co I sites, unavailable from former studies on powders. The magnetic-field-induced ferri-and ferromagnetic phases at intermediate temperature (e.g., 10 K) are identified by distinct internal fields, well accounted for by purely dipolar interactions. The vanishing transferred hyperfine field at the Co I site indicates that the Co(3+) (I) orbitals do not participate in the intrachain superexchange, in disagreement with a previous theore…

LOCAL-MOMENT AND ITINERANT ANTIFERROMAGNETISM IN THE HEAVY-FERMION SYSTEM CE(CU1-XNIX)2GE2

1992

Elastic and inelastic neutron-scattering studies on the system Ce(Cu1−xNix)2Ge2 are reported. These measurements are complemented by measurements of the magnetic susceptibility, high-field magnetization, heat capacity, thermal expansion, electrical resistivity and thermopower. The results reveal an interesting T-x phase diagram consisting of two different antiferromagnetic phases for x 0.5. Further experimental evidence for different types of antiferromagnetic ordering derives from a line-shape analysis of the quasielastic neutron-scattering intensity, from magnetization and thermopower experiments.

Magnetic properties of quasi-2D antiferromagnet {N(n-C5H11)4[MnIIFeIII(ox)3]}∞ below Néel temperature: revisited

2004

Abstract Magnetic measurements of {N(n-C 5 H 11 ) 4 [Mn II Fe III (ox) 3 ]} ∞ were carried out in the 5–300 K temperature range under different applied magnetic fields up to 50 kOe with zero-field-cooled (ZFC) and field-cooled (FC) modes. The FC and ZFC χ ( T ) plots exhibited a significantly large bifurcation below the transition temperature, which was traceable even at 50 kOe of applied magnetic field. The bifurcation temperature was found to be magnetic field dependent for the lower range of magnetic fields, which can be represented by a polynomial of magnetic field. The observed magnetic transition temperature of this compound was in good agreement with the earlier reported results. The…

Magnetic properties of some rare‐earth magnesium compounds RMg2

1981

The magnetic properties of the compounds PrMg2, NdMg2, DyMg2, and ErMg2 were studied by means of neutron diffraction at various temperatures. All these compounds give rise to ferromagnetic ordering. The absolute values of the magnetic moments in the magnetically ordered state are lower than the free‐ion values. Inelastic neutron scattering at several temperatures was studied in PrMg2 and NdMg2. Analysis of the scattering data in conjunction with the results of specific‐heat and magnetization measurements shows that PrMg2 is an induced‐moment system (G3 ground state), where quadrupolar effects carry a large weight in determining the magnetic properties. The values found for the crystal‐field…

Nuclear Magnetic Moments ofBi205,207,209Isotopes—Hyperfine Structure of the 15-dayBi2053067-Å Line

1975

Surface-induced disordering at first-order transitions in body-centered cubic binary alloys: A Monte-Carlo simulation

1990

Surface effects on the phase transition from theDO3 phase to the disordered phase are studied for a bcc Ising antiferromagnet with nearest and next-nearest neighbor exchange interactions in a magnetic field. This model can also be considered to represent binary alloys such as the FeAl-system; missing interactions near the surface translate then into surface magnetic fields. The change of the local magnetization near the surface then corresponds to “surface enrichment” of one component. For a plausible choice of parameters surface-induced disordering is found and the associated critical behavior is studied. Varying the bulk fieldH near the transition fieldHc, we find that the thickness of th…

Martensite transition and microscopic magnetism of epitaxial Ni2MnGa films

2007

AbstractA magnetically induced shape memory effect in Ni2MnGa results in huge magnetostrictive effects of several percent. Using x-ray absorption spectroscopy (XAS) and magnetic circular dichroism (XMCD) we investigated element specific magnetic moments and electronic structure of single crystalline, (110) oriented Ni2MnGa films on a-plane Al2O3 substrates in the austenite and martensite state. The structural phase transition of the samples is evident from temperature dependent x-ray diffraction and magnetization measurements. The Ni XAS differ significantly for temperatures above and below the martensite transition in agreement with published ab-initio calculations. Using XAS in transmissi…

Profesors Gunārs Sermons: biobibliogrāfiskais rādītājs

1994

Biobibliogrāfiskajā rādītājā ietverti tehnisko zinātņu doktora, profesora Gunāra Sermona publicētie darbi no 1958. līdz 1994.gadam, kā ari literatūra par viņu.

Исследование некоторых видов неоднородных МГД-течений в применении к задачам управления потоками жидкого металла

1973

Metal-Controlled Magnetoresistance at Room Temperature in Single-Molecule Devices

2017

The appropriate choice of the transition metal complex and metal surface electronic structure opens the possibility to control the spin of the charge carriers through the resulting hybrid molecule/metal spinterface in a single-molecule electrical contact at room temperature. The single-molecule conductance of a Au/molecule/Ni junction can be switched by flipping the magnetization direction of the ferromagnetic electrode. The requirements of the molecule include not just the presence of unpaired electrons: the electronic configuration of the metal center has to provide occupied or empty orbitals that strongly interact with the junction metal electrodes and that are close in energy to their F…