Noncollinear Phase of Magnetic Multilayers

MRS Proceedings ◽

10.1557/proc-475-617 ◽

1997 ◽

Vol 475 ◽

Author(s):

A. I. Morosov ◽

A. S. Sigov

Keyword(s):

Exchange Interaction ◽

Domain Structure ◽

Layered Structure ◽

Magnetic Ordering ◽

Magnetic Multilayers ◽

Ferromagnetic Phase ◽

Multilayer Structures ◽

Antiferromagnetic Phase ◽

Magnetic Layers

ABSTRACTThere is considered the dependence of magnetic ordering type in multilayer structures on the magnitude of exchange interaction between magnetic layers and the interlayer surfaces roughness. With a simple example of the three-layered structure we found the areas of the existence of such states as: (i) domain structure, (ii) noncollinear ordering of homogeneous magnetic layers, (iii) collinear ferromagnetic phase, and (iiii) collinear antiferromagnetic phase.

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Domain structure at ferromagnetic-antiferromagnetic phase transitions as superheated-undercooled state of a solid

physica status solidi (b) ◽

10.1002/pssb.2220680111 ◽

1975 ◽

Vol 68 (1) ◽

pp. 137-144

Author(s):

V. A. Popov ◽

M. L. Polyakov

Keyword(s):

Phase Transitions ◽

Domain Structure ◽

Antiferromagnetic Phase

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Magnetic Ordering of Perovskite-Like La-, Nd-, and Gd-Doped Bismuth Ferrite

MRS Advances ◽

10.1557/adv.2019.327 ◽

2019 ◽

Vol 4 (36) ◽

pp. 1989-1999 ◽

Cited By ~ 1

Author(s):

Valery Sobol ◽

Barys Korzun ◽

Olga Mazurenko ◽

Temirkhan Bizhigitov ◽

Sabit Tomaev

Keyword(s):

Magnetic Field ◽

Exchange Interaction ◽

Bismuth Ferrite ◽

Magnetic Ordering ◽

Solid State Reaction Method ◽

Nonlinear Dependence ◽

X Ray Diffraction ◽

Wide Range ◽

Pure Grade ◽

The Magnetic Field

ABSTRACTBismuth ferrite (BiFeO3) and La-, Nd- and Gd-substituted bismuth ferrite of the Bi1-xLaxFeO3, Bi1-xNdxFeO3, and Bi1-xGdxFeO3 types with the atomic part of the substitution element x equal up to 0.20 were synthesized by the solid-state reaction method using powders of oxides Bi2O3, Fe2O3, and La2O3, or Nd2O3, or Gd2O3 of pure grade quality and investigated using X-ray diffraction analysis. The magnetization was measured in the magnetic field up to 6.5⋅106 A/m at 5 and 300 K. It was found that the total substitution up to 0.20 atomic part of Bi by La, Nd, and Gd leads to the paramagnetic behavior of the doped bismuth ferrite at low temperatures in a wide range of magnetic field. Strong nonlinear dependence of magnetization on the magnetic field was detected and a ferromagnetic-like dependence of magnetization was observed for small magnetic fields. This can be explained by the exchange interaction between doping magnetic ions, as well as by the exchange interaction of these ions with ions of iron. The enhancement of magnetic properties with the increase of the content of the substitution is monotone and is more pronounced for the Bi1-xGdxFeO3 ceramics.

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Negative magnetization, complex magnetic ordering and applications of Cr-doped Co2TiO4

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06444c ◽

2020 ◽

Vol 22 (13) ◽

pp. 7058-7064

Author(s):

Q. S. Fu ◽

X. H. Chen ◽

C. Chakrabarti ◽

C. L. Li ◽

J. Zheng ◽

...

Keyword(s):

Exchange Interaction ◽

Magnetic Ordering ◽

Negative Magnetization

Negative magnetization, exchange interaction and possible applications of Cr-doped Co2TiO4 ceramics have been investigated in detail.

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Magnetic Ordering of Mn Overlayers on Fe (100)

MRS Proceedings ◽

10.1557/proc-313-381 ◽

1993 ◽

Vol 313 ◽

Author(s):

T. G. Walker ◽

H. Hopster

Keyword(s):

Surface Layer ◽

Energy Loss ◽

Magnetic Moment ◽

Magnetic State ◽

Magnetic Ordering ◽

Spectral Features ◽

Exchange Splitting ◽

Magnetic Layers ◽

Spin Polarized ◽

Electron Energy Loss

ABSTRACTSpin polarized electron energy loss spectroscopy (SPEELS) was used to probe the magnetic state of mn over layers on Fe (100). Nonzero exchange asymmetries are measured and found to oscillate with a two monolayer period as the mn overlayer thickness is varied, proving that the surface layer of the mn overlayers has a net magnetic moment and that these (100) Magnetic layers are aligned antiferromagnetically. The average exchange splitting of the mn surface layer is found to be 2.9 eV, indicating that the mn surface has a magnetic moment of the order 3 μg. In addition, oxidized mn overlayer surfaces have been studied, and the spectral features in the range 0 to 6 eV energy loss can be assigned to 3d-3d transitions of Mn2+. No indication of magnetic ordering of the MnO overlayer has been oserved.

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THE EFFECT OF PRESSURE ON THE FERROMAGNETIC PHASE TRANSITION OF EuO

Canadian Journal of Physics ◽

10.1139/p65-169 ◽

1965 ◽

Vol 43 (10) ◽

pp. 1744-1749 ◽

Cited By ~ 30

Author(s):

Richard Stevenson ◽

M. C. Robinson

Keyword(s):

Phase Transition ◽

Exchange Interaction ◽

Interaction Parameter ◽

Atmospheric Pressure ◽

Field Model ◽

Lattice Parameter ◽

Mutual Inductance ◽

Ferromagnetic Phase ◽

Ferromagnetic Phase Transition ◽

Exchange Interaction Parameter

The compressions of EuO up to 10 000 atm have been measured at 296 °K, 82 °K, and 4.2 °K. The shift in temperature of the ferromagnetic phase transition has been measured as a function of pressure by measuring the mutual inductance of a coil containing the solid. The transition occurs at about 72 °K at 10 000 atm, which is about 5 °K higher than the transition at atmospheric pressure. The results tend to substantiate the molecular field model for EuO proposed by McGuire and Shafer. An estimate is made of the variation of the exchange interaction parameter with lattice parameter, ΔJ1/Δa = −0.62 °K/Å, where J1 refers to interactions between nearest magnetic neighbors.

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DILUTED FERROMAGNETIC SEMICONDUCTORS — ORIGIN OF MAGNETIC ORDERING AND SPIN-TRANSPORT PROPERTIES

International Journal of Modern Physics B ◽

10.1142/s0217979208046116 ◽

2008 ◽

Vol 22 (01n02) ◽

pp. 104-105 ◽

Cited By ~ 1

Author(s):

TOMASZ DIETL

Keyword(s):

Diluted Magnetic Semiconductors ◽

Spin Transport ◽

Correlation Energy ◽

Tight Binding ◽

Spin Current ◽

Magnetic Ordering ◽

Exchange Interactions ◽

Ferromagnetic Phase ◽

Magnetic Characteristics ◽

Ferromagnetic Semiconductors

In the first hour of the lecture the present understanding of the origin of exchange interaction and mechanisms leading to ferromagnetic order in diluted magnetic semiconductors will be presented.1 The lecture will start by discussing energy positions of relevant open magnetic shells, including the correlation energy and excitations within the magnetic ions. The origin and magnitude of sp–d exchange interactions will then be described. This will be followed by presenting the physics of indirect exchange interactions between localized spins contrasting magnetic characteristics in the absence and in the presence of free carriers. The Zener and RKKY models of ferromagnetism will be introduced and the role of confinement, dimensionality, and spin-orbit interaction in determining properties of the ferromagnetic phase will be outlined. The second lecture will be devoted to theory of spin transport in layered structures of diluted ferromagnetic semiconductors, emphasizing the issues important for perspective spintronics devices. A recently developed theory,2 which combines a multi-orbital empirical tight-binding approach with a Landauer–Büttiker formalism will be presented. In contrast to the standard kp method, this theory describes properly the interfaces and inversion symmetry breaking as well as the band dispersion in the entire Brillouin zone, so that the essential for the spin-dependent transport Rashba and Dresselhaus terms as well as the tunneling via k points away from the zone center are taken into account. The applicability of this model for the description of tunneling magnetoresistance (TMR), resonant tunneling spectra, spin-current polarization in Esaki-Zener diodes, and domain-wall resistance will be presented. Note from Publisher: This article contains the abstract only.

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THE EFFECT OF La AND Sn DOPING ON THE STRUCTURAL AND MAGNETIC PROPERTIES OF RuSr2EuCeCu2Oz

International Journal of Modern Physics B ◽

10.1142/s0217979205028566 ◽

2005 ◽

Vol 19 (01n03) ◽

pp. 353-359 ◽

Cited By ~ 7

Author(s):

H. K. LEE ◽

H. M. Park ◽

G. V. M. Williams

Keyword(s):

Magnetic Properties ◽

Volume Fraction ◽

Magnetic Ordering ◽

Structural Data ◽

Ferromagnetic Phase ◽

X Ray Diffraction ◽

Sn Doping ◽

Ferromagnetic Component ◽

La Substitution ◽

Induced Changes

The crystal structure and magnetic properties of ( Ru 1-x Sn x) Sr 2 EuCeCu 2 O z and Ru ( Sr 2-x La x) EuCeCu 2 O z(0≤ x ≤0.1) samples have been investigated to shed light on the doping-induced changes in the magnetic properties of Ru -1222 system. We show that La substitution for Sr leads to an increase in the temperature where the ferromagnetic component is observed and a moderate suppression of the ferromagnetic component whereas Sn substitution for Ru results in a significant decrease of the volume fraction of the ferromagnetic phase as well as a decrease in the magnetic ordering temperature. The experimental results are discussed in connection with the structural data studied by Rietveld refinement of the x-ray diffraction data.

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