Role of Structural Defects on the Half-Metallic Character of Heusler Alloys and Their Junctions with Ge and GaAs

2006 ◽  
pp. 41-66 ◽  
Author(s):  
Silvia Picozzi ◽  
Alessandra Continenza ◽  
Arthur J. Freeman
Keyword(s):  
Heusler Alloys ◽  
Structural Defects ◽  
Half Metallic ◽  
Metallic Character

Possible half-metallic behavior of Co2−xCrxFeGe Heusler alloys: Theory and experiment

2021 ◽  
Vol 104 (1) ◽  
Author(s):  
R. Mahat ◽  
S. KC ◽  
U. Karki ◽  
J. Y. Law ◽  
V. Franco ◽  
...  
Keyword(s):  
Heusler Alloys ◽  
Metallic Behavior ◽  
Half Metallic ◽  
Theory And Experiment

scholarly journals The effect of pressure and alloying on half-metallicity of quaternary Heusler compounds CoMnYZ (Z = Al, Ga, and In)

2016 ◽  
Vol 34 (4) ◽  
pp. 905-915 ◽  
Author(s):  
M. Rahmoune ◽  
A. Chahed ◽  
A. Amar ◽  
H. Rozale ◽  
A. Lakdja ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Density Functional ◽  
Heusler Alloys ◽  
Band Gaps ◽  
Ferromagnetic Behavior ◽  
Full Potential ◽  
Energy Bands ◽  
Half Metallicity ◽  
Half Metallic ◽  
Electronic And Magnetic Properties

AbstractIn this work, first-principles calculations of the structural, electronic and magnetic properties of Heusler alloys CoMnYAl, CoMnYGa and CoMnYIn are presented. The full potential linearized augmented plane waves (FP-LAPW) method based on the density functional theory (DFT) has been applied. The structural results showed that CoMnYZ (Z = Al, Ga, In) compounds in the stable structure of type 1+FM were true half-metallic (HM) ferromagnets. The minority (half-metallic) band gaps were found to be 0.51 (0.158), 0.59 (0.294), and 0.54 (0.195) eV for Z = Al, Ga, and In, respectively. The characteristics of energy bands and origin of minority band gaps were also studied. In addition, the effect of volumetric and tetragonal strain on HM character was studied. We also investigated the structural, electronic and magnetic properties of the doped Heusler alloys CoMnYGa1−xAlx, CoMnYAl1−xInx and CoMnYGa1−xInx (x = 0, 0.25, 0.5, 0.75, 1). The composition dependence of the lattice parameters obeys Vegard’s law. All alloy compositions exhibit HM ferromagnetic behavior with a high Curie temperature (TC).

scholarly journals The role of Ni-Mn hybridization on the martensitic phase transitions in Mn-rich Heusler alloys

2012 ◽  
Vol 100 (17) ◽  
pp. 172403 ◽  
Author(s):  
Mahmud Khan ◽  
J. Jung ◽  
S. S. Stoyko ◽  
Arthur Mar ◽  
Abdiel Quetz ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Heusler Alloys ◽  
Martensitic Phase ◽  
Martensitic Phase Transitions

Vacancy-induced minority-spin states in half-metallic Heusler alloys

2007 ◽  
Vol 1 (5) ◽  
pp. 184-186 ◽  
Author(s):  
Kemal Özdoğan ◽  
Ersoy Şaşıoğlu ◽  
Iosif Galanakis
Keyword(s):  
Heusler Alloys ◽  
Spin States ◽  
Half Metallic ◽  
Minority Spin

scholarly journals Role of Methylation in the Induced and Spontaneous Expression of the Avian Endogenous Virusev-1: DNA Structure and Gene Products

1982 ◽  
Vol 2 (6) ◽  
pp. 638-652 ◽  
Author(s):  
Kathleen F. Conklin ◽  
John M. Coffin ◽  
Harriet L. Robinson ◽  
Mark Groudine ◽  
Robert Eisenman
Keyword(s):  
Dna Methylation ◽  
Strong Support ◽  
Reverse Transcriptase Activity ◽  
Structural Defects ◽  
Long Terminal Repeats ◽  
Control Of Gene Expression ◽  
Rna Molecules ◽  
Hypersensitive Sites ◽  
High Level

The endogenous avian provirusev-1 is widespread in white leghorn chickens. Although it has no major structural defects,ev-1 has not been associated with any phenotype and is ordinarily expressed at a very low level. In this report, we describe a chicken embryo (Number 1836) cell culture containing bothev-1 andev-6 which spontaneously expressed theev-1 provirus. This culture released a high level of noninfectious virions containing a full complement of virion structural (gag) proteins but devoid of reverse transcriptase activity or antigen. These virions contained 70S RNA closely related to the genome of Rous-associated virus type 0, but identifiable as theev-1 genome by oligonucleotide mapping. A fraction of the RNA molecules in the 70S complex were unusual in that they were polyadenylated 100 to 200 nucleotides downstream of the usual polyadenylation site. Eight sibling embryo cultures did not share this unusual phenotype with 1836, indicating that it was not inherited. However, an identical phenotype was inducible in the sibling cultures by treatment with 5-azacytidine, an inhibitor of DNA methylation, and the induced expression was stable for more than 10 generations. Analysis of chromatin structure and DNA methylation of theev-1 provirus in 1836 cells revealed the presence (in a fraction of the proviruses) of both DNase I hypersensitive sites in the long terminal repeats and ingagand a pattern of cleavage sites for methyl-sensitive restriction endonuclease not found in a nonexpressing sibling. These results lend strong support to the role of DNA methylation in the control of gene expression. Additionally, they explain the lack of phenotype associated withev-1 as due to a combination of its low expression and defectiveness inpolandenv.

Sign in / Sign up

Export Citation Format

Share Document