Ferromagnetic ordering and magnetic anisotropy of a Mn monolayer on Nb(001)

The multilayer films [Al2O3/tCo Co/tPt Pt]N, produced by sequential deposition of Co and Pt on alumina consist in layers of CoPt alloyed nanoparticles. They show perpendicular magnetic anisotropy (PMA) below a freezing temperature Tf, an asperomagnetic-like phase below that temperature, and hard ferromagnetic ordering below a transition temperature T1 < Tf. A single layer granular film (N = 1) with deposition thicknesses tCo=0.7 nm, tPt=1.5 nm and particle diameter of 3 nm is presently studied. SQUID magnetometry shows that a single layer presents the three phases as well. Para-, aspero-and ferromagnetic phases are observed upon lowering the temperature, with transition temperatures Tf ≈ 375 K and T1 ≈ 200 K, respectively. In addition, the PMA persists, proving that there is no interlayer coupling in the multilayer system. SQUID results also reveal a core-shell structure in the CoPt nanoparticles.

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ChemInform Abstract: Crystal Structure, Ferromagnetic Ordering and Magnetic Anisotropy for Two Cyano-Bridged Bimetallic Compounds of Formula Mn2(H2O)5Mo (CN)7×nH2O.

ChemInform ◽

10.1002/chin.199831003 ◽

2010 ◽

Vol 29 (31) ◽

pp. no-no

Author(s):

J. LARIONOVA ◽

J. SANCHIZ ◽

S. GOHLEN ◽

L. OUAHAB ◽

O. KAHN

Keyword(s):

Crystal Structure ◽

Magnetic Anisotropy ◽

Ferromagnetic Ordering ◽

Bimetallic Compounds

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Crystal structure, ferromagnetic ordering and magnetic anisotropy for two cyano-bridged bimetallic compounds of formula Mn2(H2O)5Mo(CN)7·nH2O

Chemical Communications ◽

10.1039/a801644e ◽

1998 ◽

pp. 953-954 ◽

Cited By ~ 43

Author(s):

Joulia Larionova ◽

Joaquin Sanchiz ◽

Olivier Kahn ◽

Stéphane Gohlen ◽

Lahcène Ouahab

Keyword(s):

Crystal Structure ◽

Magnetic Anisotropy ◽

Ferromagnetic Ordering ◽

Bimetallic Compounds

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Compositional Dependence of Magnetocrystalline Anisotropy in Fe-, Co-, and Cu-Alloyed Ni-Mn-Ga

Metals ◽

10.3390/met12010133 ◽

2022 ◽

Vol 12 (1) ◽

pp. 133

Author(s):

Michal Rameš ◽

Vít Kopecký ◽

Oleg Heczko

Keyword(s):

Magnetic Anisotropy ◽

Magnetocrystalline Anisotropy ◽

Compositional Dependence ◽

Transformation Temperatures ◽

Transitional Metals ◽

Polycrystalline Alloys ◽

Ferromagnetic Ordering

The key for the existence of magnetic induced reorientation is strong magnetocrystalline anisotropy, i.e., the coupling between ferroelastic and ferromagnetic ordering. To increase the transformation temperatures and thus functionality, various elemental alloying in Ni-Mn-Ga is tried. We analyzed more than twenty polycrystalline alloys alloyed by small amount (up to 5atom%) of transitional metals Co, Fe, Ni, and Cu for the value of magnetic anisotropy in search of general trends with alloying. In agreement with previous reports, we found that maximum anisotropy occurs at stoichiometric Ni2MnGa and any alloying decreases its value. The strongest decrease of the anisotropy is observed in the case where the alloyed elements substitute Ga.

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TEM Study of Co/Pd and Co/Au Multilayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151015 ◽

1993 ◽

Vol 51 ◽

pp. 1036-1037

Author(s):

A.E.M. De Veirman ◽

F.J.G. Hakkens ◽

W.M.J. Coene ◽

F.J.A. den Broeder

Keyword(s):

Magnetic Anisotropy ◽

Ion Beam ◽

Perpendicular Magnetic Anisotropy ◽

Optical Recording ◽

Magnetic Multilayer ◽

Ion Beam Sputtering ◽

Cross Sectional ◽

Transmission Electron ◽

Beam Sputtering ◽

Substrate Temperatures

There is currently great interest in magnetic multilayer (ML) thin films (see e.g.), because they display some interesting magnetic properties. Co/Pd and Co/Au ML systems exhibit perpendicular magnetic anisotropy below certain Co layer thicknesses, which makes them candidates for applications in the field of magneto-optical recording. It has been found that the magnetic anisotropy of a particular system strongly depends on the preparation method (vapour deposition, sputtering, ion beam sputtering) as well as on the substrate, underlayer and deposition temperature. In order to get a better understanding of the correlation between microstructure and properties a thorough cross-sectional transmission electron microscopy (XTEM) study of vapour deposited Co/Pd and Co/Au (111) MLs was undertaken (for more detailed results see ref.).The Co/Pd films (with fixed Pd thickness of 2.2 nm) were deposited on mica substrates at substrate temperatures Ts of 20°C and 200°C, after prior deposition of a 100 nm Pd underlayer at 450°C.

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