Cation vacancy and magnetic properties of ZnFe2O4 microspheres

Based on first principle FP-LAPW calculations, the electronic structure and magnetic properties of ZnO with Zn cation vacancy has been investigated. We find that the cation vacancy defect can induce a magnetic moment of about 2μB/supercell. The magnetic moment mainly comes from 2p-orbitals of O atoms which surround the Zn vacancy. We also find that the two Zn vacancies in ZnO always coupled Ferro-magnetically. Furthermore, the system shows half metallic Ferro-magnetic properties with high Curie temperature.

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Strain Manipulated Magnetic Properties in ZnO and GaN Induced by Cation Vacancy

Journal of Electronic Materials ◽

10.1007/s11664-016-4482-9 ◽

2016 ◽

Vol 45 (7) ◽

pp. 3300-3306 ◽

Cited By ~ 1

Author(s):

Yanqin Gai ◽

Jiaping Jiang ◽

Yuxi Wu ◽

Gang Tang

Keyword(s):

Magnetic Properties ◽

Cation Vacancy

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Electronic and magnetic properties of the cation vacancy defect inm−HfO2

Physical Review B ◽

10.1103/physrevb.92.205124 ◽

2015 ◽

Vol 92 (20) ◽

Cited By ~ 14

Author(s):

Keith P. McKenna ◽

David Muñoz Ramo

Keyword(s):

Magnetic Properties ◽

Cation Vacancy ◽

Vacancy Defect ◽

Electronic And Magnetic Properties

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The Effect of Reducing Time on the Magnetoresistance of Manganite La0.67Sr0.20Cu0.10□0.03MnO3at a Temperature of 30°C

Journal of Nanomaterials ◽

10.1155/2012/426037 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5

Author(s):

Hongwei Zhao ◽

Lichun Hu ◽

Zhanxin Zhang

Keyword(s):

Magnetic Field ◽

Magnetic Properties ◽

Temperature Region ◽

Colossal Magnetoresistance ◽

Cation Vacancy ◽

Sol Gel ◽

Hydrogen Atmosphere ◽

Argon Atmosphere ◽

Parent Materials ◽

Electrical And Magnetic Properties

La0.67Sr0.20Cu0.10□0.03MnO3(“□” representing cation vacancy) polycrystalline manganite powder was synthesized by sol-gel method, which we used as parent materials. After reduced in hydrogen atmosphere for 30 and 60 minutes at a temperature of 400°C, the series bulk samples were obtained by sintering in argon atmosphere for 12 hours at 1100°C. The structure, electrical and magnetic properties, and colossal magnetoresistance of samples were researched in detail. Experiment results indicate that under an applied magnetic field of 1.8 T, the two bulk samples sintered in Ar atmosphere for 12 hours at 1100°C, with the powder reduced for 30 and 60 minutes in 400°C hydrogen atmosphere for La0.67Sr0.20Cu0.10□0.03MnO3parent powders, respectively, have the stable MR (11.0 ± 0.3)% and (10.0 ± 0.5)% in temperature region from 270 K to 330 K. this is important for the potential application of this kind of magnetoresistance materials.

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AEM analysis of crystallization in Ti-based amorphous alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075142 ◽

1983 ◽

Vol 41 ◽

pp. 270-271

Author(s):

A.R. Pelton ◽

A.F. Marshall ◽

Y.S. Lee

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Amorphous Materials ◽

Isothermal Annealing ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Current Interest ◽

Amorphous Films ◽

Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

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Microstructure in soft magnetic E3 (S1, Al) (Sendust) alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105916 ◽

1988 ◽

Vol 46 ◽

pp. 770-771

Author(s):

June D. Kim

Keyword(s):

Electron Microscopy ◽

Magnetic Properties ◽

Ternary Phase Diagram ◽

Vertical Tube ◽

Vacuum Induction Melting ◽

Induction Melting ◽

Soft Magnetic ◽

Quenching Temperature ◽

Thin Foils ◽

Vertical Tube Furnace

Iron-base alloys containing 8-11 wt.% Si, 4-8 wt.% Al, known as “Sendust” alloys, show excellent soft magnetic properties. These magnetic properties are strongly dependent on heat treatment conditions, especially on the quenching temperature following annealing. But little has been known about the microstructure and the Fe-Si-Al ternary phase diagram has not been established. In the present investigation, transmission electron microscopy (TEM) has been used to study the microstructure in a Sendust alloy as a function of temperature.An Fe-9.34 wt.% Si-5.34 wt.% Al (approximately Fe3Si0.6Al0.4) alloy was prepared by vacuum induction melting, and homogenized at 1,200°C for 5 hrs. Specimens were heat-treated in a vertical tube furnace in air, and the temperature was controlled to an accuracy of ±2°C. Thin foils for TEM observation were prepared by jet polishing using a mixture of perchloric acid 15% and acetic acid 85% at 10V and ∼13°C. Electron microscopy was performed using a Philips EM 301 microscope.

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