X-ray examination, electrical and magnetic properties of R3Co single crystals (R ≡ Y, Gd, Dy and Ho)

In this research, influence of adding Li2CO3 (at 0%, 2%, 4%, 6%) on electrical and magnetic properties of [Formula: see text][Formula: see text]Fe2O4 (with 60% Ni and 40% Mg) ferrite has been studied. The samples are prepared by solid state reaction method and sintered at 1300∘C for 6[Formula: see text]h. X-ray diffraction (XRD) patterns show the samples belong to single-phase cubic structure without any impurity phase. The magnetic properties (saturation magnetization and coercivity) of the samples have been investigated by VSM and found that the higher concentration of Li2CO3 reduces the hysteresis loss. DC resistivity increases with Li2CO3 contents whereas it decreases initially and then becomes constant at lower value with temperature which indicates that the studied samples are semiconductor. The dielectric dispersion occurs at a low-frequency regime and the loss peaks are formed in a higher frequency regime, which are due to the presence of resonance between applied frequency and hopping frequency of charge carriers. Notably, the loss peaks are shifted to the lower frequency with Li2CO3 additions.

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Single crystal growth and magnetic properties of Co-doped ZnNb2O6

Modern Physics Letters B ◽

10.1142/s0217984919502749 ◽

2019 ◽

Vol 33 (23) ◽

pp. 1950274

Author(s):

Ying Liu ◽

Dapeng Xu ◽

Huamin Yu ◽

Tian Cui ◽

Liang Li

Keyword(s):

Magnetic Properties ◽

Single Crystals ◽

Photoelectron Spectroscopy ◽

Physical Property Measurement System ◽

Physical Property ◽

X Ray Diffraction ◽

Zone Method ◽

X Ray ◽

Structure Formula ◽

Property Measurement

The columbite structure [Formula: see text] single crystals have been successfully grown by using the optical floating zone method. The as-grown crystals are characterized by X-ray diffraction (XRD), Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS). All these analyses show that the doping Co ions do not disturb the structure of columbite [Formula: see text] and some [Formula: see text] ions are substituted by transition metal [Formula: see text] ions without any other impurities. The magnetic properties of as-grown [Formula: see text] crystals have been investigated using Physical Property Measurement System (PPMS). The effective magnetic moment of [Formula: see text] crystals is [Formula: see text], indicating that [Formula: see text] ions present in [Formula: see text] single crystals are in mixed HS and LS states. The ferromagnetic, antiferromagnetic and paramagnetic characters of as-grown crystals are also discussed.

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Application of Gel Technology in Preparation of High-Tc Perovskite Superconductors

MRS Proceedings ◽

10.1557/proc-99-253 ◽

1987 ◽

Vol 99 ◽

Author(s):

R. S. Liu ◽

G. C. Lin ◽

H. M. Sung ◽

Y. C. Chen ◽

O. C. C. Lin

Keyword(s):

Magnetic Properties ◽

Magnetic Susceptibility ◽

Diffraction Analysis ◽

Dicarboxylic Acids ◽

X Ray Diffraction ◽

Chemical Homogeneity ◽

High Tc ◽

X Ray ◽

Electrical And Magnetic Properties ◽

High Degree

ABSTRACTLa-Ba-Cu-O and Y-Ba-Cu-O superconducting systems have been successfully prepared by gel techniques with high degree of chemical homogeneity. The precursor gel was synthesized from mixture of the corresponding metallic nitrates and di-carboxylic acids. The sintered oxides prepared from the different dicarboxylic acids were all Tc = 90K perovskite superconductors. However differences in electrical and magnetic properties were also observed. Effects due to the different acids elucidated by magnetic susceptibility measurements and X-ray diffraction analysis will be discussed.

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Superconductivity and Normal-State Properties of (Y1-x-yZrxCay)Ba2Cu3O7-δ Compounds

Modern Physics Letters B ◽

10.1142/s0217984998001384 ◽

1998 ◽

Vol 12 (28) ◽

pp. 1175-1183 ◽

Cited By ~ 2

Author(s):

I. Gr. Deac ◽

A. V. Pop ◽

V. Pop ◽

R. Tetean ◽

D. Kovacs ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetic Susceptibility ◽

Powder Diffraction ◽

Normal State ◽

Lattice Parameters ◽

Temperature Dependent ◽

Dopant Content ◽

X Ray ◽

Electrical And Magnetic Properties ◽

Normal State Properties

The electrical and magnetic properties of ( Y 1-x-y Zr x Ca y) Ba 2 Cu 3 O 7-δ ceramics are investigated by using resistivity, ac and dc susceptibility measurements. X-ray powder diffraction has been used to find the lattice parameters of the samples. The samples are orthorhombic, except the sample with x=0.15 and y=0.2 which is tetragonal. All the samples are superconducting. There is no significant change in Tc for the Zr-doped ( Y 1-x Zr x) Ba 2 Cu 3 O 7-δ samples, while for the ( Y 0.85-y Zr 0.15 Ca y) Ba 2 Cu 3 O 7-δ compounds the Tc decrease with the dopant content and they show temperature dependent dc magnetic susceptibility, in the normal state.

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Combining CXMD and XSW to study magnetic and geometric properties of thin films: Gd/Fe(100)

Journal of Synchrotron Radiation ◽

10.1107/s0909049598018317 ◽

1999 ◽

Vol 6 (2) ◽

pp. 105-111 ◽

Cited By ~ 2

Author(s):

R. Treusch ◽

W. Drube ◽

G. Materlik

Keyword(s):

Thin Films ◽

Magnetic Properties ◽

Single Crystals ◽

Long Range ◽

Geometric Structure ◽

High Flux ◽

X Rays ◽

Magnetic Polarization ◽

X Ray ◽

Magnetic Dichroism

The magnetic and geometric structure of 1–5 monolayers (ML) of Gd on Fe(100) single crystals has been investigated using synchrotron X-rays between 4 and 8 keV. Choosing a high-flux wiggler beamline made it possible to analyse the magnetic properties by studying the circular X-ray magnetic dichroism (CXMD) and, in addition, to apply the X-ray standing-wave (XSW) technique to elucidate the geometric structure of the overlayers. CXMD reveals that Gd couples antiferromagnetically to the Fe substrate and that 2 ML Gd at 243 K yield a magnetization of ∼22% with respect to the saturation value of a thick Gd foil at 123 K. A magnetic polarization of the Gd pertains even at 308 K. While LEED investigations do not show any long-range lateral order of the Gd film, XSW measurements reveal an ordering of Gd perpendicular to the (100) surface of Fe.

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