Magnetic Structure of Ion-Beam Imprinted Stripe Domains Determined by Neutron Scattering

We present a detailed analysis of the in-plane magnetic vector configuration in head-to-head/tail-to-tail stripe domain patterns of nominal 5 μm width. The patterns have been created by He-ion bombardment induced magnetic patterning of a CoFe/IrMn3 exchange bias thin-film system. Quantitative information about the chemical and magnetic structure is obtained from polarized neutron reflectometry (PNR) and off-specular scattering (OSS). The technique provides information on the magnetic vector orientation and magnitude along the lateral coordinate of the sample, as well as the chemical and magnetic layer structure as a function of depth. Additional sensitivity to magnetic features is obtained through a neutron wave field resonance, which is fully accounted for in the presented analysis. The scattering reveals a domain width imbalance of 5.3 to 3.7 μm of virgin and bombarded stripes, respectively. Further, we report that the magnetization in the bombarded stripe significantly deviates from the head-to-head arrangement. A domain wall of 0.6 μm with homogeneous magnetization direction is found to separate the two neighboring domains. The results contain detailed information on length scales and magnetization vectors provided by PNR and OSS in absolute units. We illustrate the complementarity of the technique to microscopy techniques for obtaining a quantitative description of imprinted magnetic domain patterns and illustrate its applicability to different sample systems.

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The direct determination of magnetic domain wall profiles using a split detector STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109471 ◽

1978 ◽

Vol 36 (1) ◽

pp. 466-467

Author(s):

J.N. Chapman ◽

P.E. Batson ◽

E.M. Waddell ◽

R.P. Ferrier

Keyword(s):

Electron Microscope ◽

Domain Wall ◽

Transmission Electron Microscope ◽

Domain Walls ◽

Photographic Plate ◽

Magnetic Domain ◽

Direct Determination ◽

Quantitative Information ◽

Scanning Transmission Electron Microscope ◽

Transmission Electron

By far the most commonly used mode of Lorentz microscopy in the examination of ferromagnetic thin films is the Fresnel or defocus mode. Use of this mode in the conventional transmission electron microscope (CTEM) is straightforward and immediately reveals the existence of all domain walls present. However, if such quantitative information as the domain wall profile is required, the technique suffers from several disadvantages. These include the inability to directly observe fine image detail on the viewing screen because of the stringent illumination coherence requirements, the difficulty of accurately translating part of a photographic plate into quantitative electron intensity data, and, perhaps most severe, the difficulty of interpreting this data. One solution to the first-named problem is to use a CTEM equipped with a field emission gun (FEG) (Inoue, Harada and Yamamoto 1977) whilst a second is to use the equivalent mode of image formation in a scanning transmission electron microscope (STEM) (Chapman, Batson, Waddell, Ferrier and Craven 1977), a technique which largely overcomes the second-named problem as well.

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The Influences of Depositing Angles on TbFe Film Magnetic and Magnetostrictive Characteristics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3757 ◽

2005 ◽

Vol 475-479 ◽

pp. 3757-3760

Author(s):

Hong Chuan Jiang ◽

Wan Li Zhang ◽

Bin Peng ◽

Wen Xu Zhang ◽

Shi Qing Yang

Keyword(s):

External Field ◽

Magnetic Domain ◽

Grain Morphology ◽

Dc Magnetron Sputtering ◽

Easy Magnetization ◽

Magnetization Direction ◽

Saturation Field ◽

Domain Structures ◽

Columnar Grain ◽

Easy Magnetization Direction

In this paper, the influences of depositing angles on TbFe film magnetic and magnetostrictive characteristics were discussed. TbFe films were deposited by DC magnetron sputtering. With the decrease of depositing angles from 900 to 150, TbFe film in-plane magnetization measured at 1600kA.m-1 external field is greatly increased. With the decrease of depositing angles from 900 to 150, the magnetostrictive saturation field is decreased. TbFe film in-plane magnetostriction is improved when depositing angles are changed from 900 to 150. Magnetic domain structures detected by MFM indicates that film easy magnetization direction is gradually changed from perpendicular to parallel with the decrease of depositing angles. The variation of film magnetic and magnetostrictive performances can be explained by the oblique anisotropy associated with columnar grain morphology of the films.

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Relationship between tunnel magnetoresistance and magnetic layer structure in EuO-based tunnel junctions investigated using polarized neutron reflectivity

Journal of Applied Physics ◽

10.1063/1.2837873 ◽

2008 ◽

Vol 103 (7) ◽

pp. 07A719 ◽

Cited By ~ 7

Author(s):

S. M. Watson ◽

T. S. Santos ◽

J. A. Borchers ◽

J. S. Moodera

Keyword(s):

Tunnel Junctions ◽

Layer Structure ◽

Magnetic Layer ◽

Neutron Reflectivity ◽

Tunnel Magnetoresistance ◽

Polarized Neutron

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Thermal-Driven Evolution of Magnetic Domain Structures in Ultrathin Films

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.112.101 ◽

2006 ◽

Vol 112 ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

V. Zablotskii ◽

Andrzej Maziewski ◽

T. Polyakova

Keyword(s):

Ultrathin Films ◽

Characteristic Length ◽

Magnetic Domain ◽

Magnetic Films ◽

Spin Reorientation ◽

Stripe Domain ◽

Domain Structures ◽

Increasing Temperature ◽

Domain Period ◽

Key Parameter

The thermal-driven evolution of stripe domain structures in ultrathin magnetic films is analyzed with regard to temperature dependencies of the film magnetic parameters. In the vicinity of the Curie temperature or points of the spin reorientation the equilibrium stripe domain period was found to exponentially decrease with increasing temperature. It is shown that the temperature dependence of the characteristic length is the key parameter controlling the domain period changes. Irreversible and reversible changes of the domain period as well as the so-called inverse domain melting are discussed.

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Adjacent Layer Composition Effects on Fetbco Thin Film Magnetic Properties

MRS Proceedings ◽

10.1557/proc-384-123 ◽

1995 ◽

Vol 384 ◽

Author(s):

Michael B. Hintz

Keyword(s):

Magnetic Properties ◽

Ion Beam ◽

Magnetic Layer ◽

Magnetic Behavior ◽

Relative Magnitude ◽

Adjacent Layer ◽

Energy Product ◽

Magnetic Layers ◽

20 Nm ◽

Layer Composition

ABSTRACTThe magneto-optical (MO) layer in current rare earth-transition metal (RE-TM) based MO recording media is typically 20 nm to 60 nm thick. It has been suggested, however, that media structures employing a multiplicity of thinner MO layers may be advantageous, e.g., for multilevel recording applications [1] or media noise reduction [2]. As magnetic layer thickness is reduced, interactions among magnetic layers and adjacent materials can have an increasingly large influence on magnetic properties; in many instances, these interactions can dominate the observed magnetic behavior.As a means of studying MO layer - adjacent layer interactions, we have used thin (≈3 nm) films of several materials to separate single 24 nm thick ion-beam-deposited FeTbCo layers into N thinner layers of 24/N nm thickness (N × 24/N). As N increases, the FeThCo magnetic properties generally change; however, the relative magnitude of the changes is strongly dependent upon the adjacent layer composition. Magnetization (Ms), energy product (MsHc) at 30 C and Curie temperature data for 1 × 24 nm structures and 6 × 4 nm structures are compared and discussed for specimens employing SiCx, Six, YOx, HfOx, Si and SiOx adjacent layer materials.

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Study on Hydrogen Evolution Properties of Carbon Supported PtCu-LaOx Membrane Electrode Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.2344 ◽

2011 ◽

Vol 311-313 ◽

pp. 2344-2347

Author(s):

Bin Yang ◽

Tao Xu

Keyword(s):

Hydrogen Evolution ◽

Double Layer ◽

Current Density ◽

Electrode Materials ◽

Layer Structure ◽

Ion Beam ◽

Exchange Current ◽

Exchange Current Density ◽

Membrane Electrode ◽

Membrane Electrodes

In order to reduce production cost of making H2, one of the key points was to reduce Pt loading in Pt/C catalytic electrode. In our study, a new type of Pt/C membrane electrodes, PtCu-LaOx/C (abbr. PCL) and LaOx-PtCu/C (abbr. LPC) double-layer structure, in which Pt nanometer particles homogeneously dispersed on the surface of carbonaceous substrates were manufactured by Ion Beam Sputtering (IBS) technology. The hydrogen evolution polarization curves of these double-layer membrane electrodes were tested by three-electrode system, and the optimal sample was selected by the calculation results of their exchange current density (i0) and decomposition voltage (Ed). It was found that PCL with Pt loading less than 0.05mg/cm2 (the electrode area) whose decomposition voltage and exchange current density was -0.204(V vs SCE) and 147.0μA/cm2 respectively in balanced condition.

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Detection of shape and sizes of magnetic impurity based on the shape of magnetic domain configuration

International Journal of Modern Physics B ◽

10.1142/s0217979216500818 ◽

2016 ◽

Vol 30 (12) ◽

pp. 1650081 ◽

Cited By ~ 6

Author(s):

M. L. Akimov ◽

P. A. Polyakov ◽

A. A. Banishev ◽

N. N. Usmanov

Keyword(s):

Domain Structure ◽

Magnetic Impurity ◽

Magnetic Domain ◽

Magnetic Film ◽

Magnetic Shielding ◽

Stripe Domain ◽

Magnetostatic Field ◽

Domain Configuration ◽

Stripe Domain Structure ◽

Shape And Size

The phenomenon of domain magnetic shielding by the magnetic sample of external and intrinsic magnetostatic field has been revealed. In this work, we investigate the possibility for detection of the shape and size of magnetic impurity based on the shape of magnetic domain configuration in magnetic film. We show that due to the influence of magnetostatic field of stripe domain structure in magnetic film on the magnetostatic field of magnetic impurity, one can determine the shape and size of this impurity.

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Studies of magnetic structure of written bits using Lorentz microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154809 ◽

1989 ◽

Vol 47 ◽

pp. 566-567

Author(s):

T.A. Nguyen ◽

P.S. Alexopoulos ◽

S.E. Lambert ◽

I.L. Sanders ◽

C. Hwang

Keyword(s):

Magnetic Structure ◽

Magnetic Layer ◽

Information Storage ◽

Detailed Knowledge ◽

Magnetic Media ◽

Lorentz Microscopy ◽

Magnetic Structures ◽

Transition Zones ◽

Size Limits ◽

Fringing Fields

Understanding the fundamental size limits of magnetic bits for high density information storage requires detailed knowledge of the magnetic structure of the written bits. Bit definition, fringing fields and magnetic structures at and between transition zones are important information for the design of future magnetic media. Using Lorentz microscopy, we have investigated these parameters in Co-alloy thin films as a function of recording density (200, 600 and 1000 fc/mm) on discrete tracks of widths from 0.6 to 10 μm.The magnetic media consist of a Co-alloy and an underlayer prepared by sputtering onto a sputter-cleaned Si disk. The magnetic parameters for the magnetic layer are: coercive field Hc = 950 Oe, remanent magnetization Mr = 533 emu/cm3 and media thickness d = 400 Å. The discrete tracks were formed on the surface of the disk by sputter-etching through a photoresist mask to remove media between the tracks. This permits the recording characteristics of tracks as narrow as 0.6 μm to be investigated using heads of conventional width.

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STRUCTURES AND MECHANICAL PROPERTIES OF MODULATED ZrB2/W AND ZrB2/WNx NANOMULTILAYERS

International Journal of Modern Physics B ◽

10.1142/s0217979210063958 ◽

2010 ◽

Vol 24 (01n02) ◽

pp. 34-42 ◽

Cited By ~ 2

Author(s):

M. TAN ◽

D. J. LI ◽

G. Q. LIU ◽

L. DONG ◽

X. Y. DENG ◽

...

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Significant Contribution ◽

Layer Structure ◽

Ion Beam ◽

X Ray Diffraction ◽

Cross Sectional ◽

Composition Modulation ◽

Ion Beam Assisted Deposition ◽

Xrd Patterns

ZrB 2, W , WN x coatings and ZrB 2/ W , ZrB 2/ WN x multilayered coatings have been synthesized by ion beam assisted deposition at room temperature. X-ray diffraction (XRD), XP-2 surface profiler, scanning electron microscopy (SEM) and nano indenter were employed to investigate the influence of modulation periods and N + beam bombardment on microstructure and mechanical properties of the coatings. The low-angle XRD patterns and cross-sectional SEM indicate a well-defined composition modulation and layer structure of the multilayers. The multilayers with modulation periods ranging from 9 to 16 nm without N + bombardment possessed higher hardness and elastic modulus than the rule-of-mixtures value of monolithic ZrB 2 and W coatings. The highest hardness was 24 GPa. N + bombardment to growing multilayers gave a significant contribution to mechanical property enhancement. When modulation period is 9.6 nm, ZrB 2/ WN x multilayer with 200 eV N + bombardment reveals the highest hardness (30.2 GPa) and elastic modulus. This hardest multilayer also showed the improved residual stress and fracture resistance.

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