Factors Governing the Propagation Direction and Spin-Rotation Plane of Noncollinear Magnetic Structures: A Helix vs Cycloid in Doubly Ordered Perovskites NaYMnWO6 and NaYNiWO6

Muon spin rotation ( μ SR) spectra recorded for manganese silicide MnSi and interpreted in terms of a quantitative analysis constrained by symmetry arguments were recently published. The magnetic structures of MnSi in zero-field at low temperature and in the conical phase near the magnetic phase transition were shown to substantially deviate from the expected helical and conical structures. Here, we present material backing the previous results obtained in zero-field. First, from simulations of the field distributions experienced by the muons as a function of relevant parameters, we confirm the uniqueness of the initial interpretation and illustrate the remarkable complementarity of neutron scattering and μ SR for the MnSi magnetic structure determination. Second, we present the result of a μ SR experiment performed on MnSi crystallites grown in a Zn-flux and compare it with the previous data recorded with a crystal obtained from Czochralski pulling. We find the magnetic structure for the two types of crystals to be identical within experimental uncertainties. We finally address the question of a possible muon-induced effect by presenting transverse field μ SR spectra recorded in a wide range of temperature and field intensity. The field distribution parameters perfectly scale with the macroscopic magnetization, ruling out a muon-induced effect.

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Contrast of Filament Bright Rims

International Astronomical Union Colloquium ◽

10.1017/s0252921100025628 ◽

1994 ◽

Vol 144 ◽

pp. 365-367

Author(s):

E. V. Kononovich ◽

O. B. Smirnova ◽

P. Heinzel ◽

P. Kotrč

Keyword(s):

High Altitude ◽

Line Profile ◽

Line Center ◽

Magnetic Structures ◽

The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

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Dislocations, Ordering and Antiferromagnetic Domains in MnO

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069600 ◽

1970 ◽

Vol 28 ◽

pp. 522-523

Author(s):

D. J. Barber ◽

R. G. Evans

Keyword(s):

Electron Diffraction ◽

Single Crystal ◽

Optical Microscopy ◽

Defect Chemistry ◽

Magnetic Structures ◽

Optically Transparent ◽

Magnetic Features ◽

Antiferromagnetic Domains

Manganese (II) oxide, MnO, in common with CoO, NiO and FeO, possesses the NaCl structure and shows antiferromagnetism below its Neel point, Tn∼ 122 K. However, the defect chemistry of the four oxides is different and the magnetic structures are not identical. The non-stoichiometry in MnO2 small (∼2%) and below the Tn the spins lie in (111) planes. Previous work reported observations of magnetic features in CoO and NiO. The aim of our work was to find explanations for certain resonance results on antiferromagnetic MnO.Foils of single crystal MnO were prepared from shaped discs by dissolution in a mixture of HCl and HNO3. Optical microscopy revealed that the etch-pitted foils contained cruciform-shaped precipitates, often thick and proud of the surface but red-colored when optically transparent (MnO is green). Electron diffraction and probe microanalysis indicated that the precipitates were Mn2O3, in contrast with recent findings of Co3O4 in CoO.

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New type of domain boundaries in multilayer magnetic structures

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0169.199908h.0922 ◽

1999 ◽

Vol 169 (8) ◽

pp. 922 ◽

Cited By ~ 1

Author(s):

Aleksandr I. Morozov ◽

Aleksandr S. Sigov

Keyword(s):

Magnetic Structures ◽

Domain Boundaries ◽

New Type

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Effect of Reaction Time on Microwave Absorption Properties of Fe3O4 Hollow Spheres Synthesized via Ostwald Ripening

Materials ◽

10.3390/ma12182921 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2921 ◽

Cited By ~ 1

Author(s):

Wei Huang ◽

Yujiang Wang ◽

Shicheng Wei ◽

Bo Wang ◽

Yi Liang ◽

...

Keyword(s):

Reaction Time ◽

Microwave Absorption ◽

Ostwald Ripening ◽

Impedance Matching ◽

Hollow Spheres ◽

Absorption Properties ◽

Microwave Absorption Properties ◽

Magnetic Structures ◽

Absorption Performance ◽

Microwave Absorption Performance

Hollow magnetic structures have great potential to be used in the microwave absorbing field. Herein, Fe3O4 hollow spheres with different levels of hollowness were synthesized by the hydrothermal method under Ostwald ripening effect. In addition to their microstructures, the microwave absorption properties of such spheres were investigated. The results show that the grain size and hollowness of Fe3O4 hollow spheres both increase as the reaction time increases. With increasing hollowness, the attenuation ability of electromagnetic wave of Fe3O4 spheres increases first and then decreases, finally increases sharply after the spheres break down. Samples with strong attenuation ability can achieve good impedance matching, which it does preferentially as the absorber thickness increases. Fe3O4 hollow spheres show the best microwave absorption performance when the reaction time is 24 h. The minimum reflection loss (RL (min)) can reach −40 dB, while the thickness is only 3.2 mm.

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Sol–gel magnetite inks for inkjet printing

Journal of Materials Chemistry C ◽

10.1039/c9tc00311h ◽

2019 ◽

Vol 7 (21) ◽

pp. 6426-6432 ◽

Cited By ~ 5

Author(s):

Denis S. Kolchanov ◽

Vladislav Slabov ◽

Kirill Keller ◽

Ekaterina Sergeeva ◽

Mikhail V. Zhukov ◽

...

Keyword(s):

Inkjet Printing ◽

Sol Gel ◽

Device Fabrication ◽

Magnetic Device ◽

Magnetic Structures

The article describes an easy-to-implement and print-ready composition for inkjet printing of magnetic structures, which can be used for security printing, coding, and marking, magnetic device fabrication or creation of micro-antennas.

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