Magnetization Control and Transfer of Spin-Polarized Cooper Pairs into a Half-Metal Manganite

We investigated transport characteristics of composite that consist of the superconductor MgB2 and ferromagnetic half-metallic nanoparticles La0.7Ca0.3MnO3 (LCMO). The experiments were carried out in a wide temperature range with different volume content of the magnetic impurity. It was found that over 25% of the impurity manganite breaches percolation paths of the diboride magnesium. This leads to a considerable broadening of the MgB2 superconducting transition and the formation of the network of contacts through the ferromagnetic inclusions. This result shows the possibility of the spin - activated surface realization on the superconductor - manganite boundary. It's allowing the free transition of Cooper pairs with s wave symmetry of the order parameter in a ferromagnet with 100% spin-polarized carriers.

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Robust and Efficient Electrical Injection of Spin-Polarized Carriers from a Zero-Spin-Gap Half-Metal V2NiAl into n-Si at Room Temperature

ACS Applied Electronic Materials ◽

10.1021/acsaelm.0c00625 ◽

2020 ◽

Vol 2 (10) ◽

pp. 3299-3306

Author(s):

Nilay Maji ◽

Tapan Kumar Nath

Keyword(s):

Room Temperature ◽

Spin Gap ◽

Half Metal ◽

Spin Polarized ◽

Electrical Injection

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Quasiparticle density of states in a half metal in the presence of odd-frequency Cooper pairs

physica status solidi (a) ◽

10.1002/pssa.200776451 ◽

2008 ◽

Vol 205 (5) ◽

pp. 1023-1025 ◽

Cited By ~ 2

Author(s):

Yasuhiro Asano ◽

Takehito Yokoyama ◽

Yukio Tanaka ◽

Alexander A. Golubov

Keyword(s):

Density Of States ◽

Cooper Pairs ◽

Half Metal ◽

Quasiparticle Density

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JOSEPHSON π-STATE DUE TO SPIN-ACTIVE JUNCTION INTERFACE

International Journal of Modern Physics B ◽

10.1142/s0217979207044615 ◽

2007 ◽

Vol 21 (18n19) ◽

pp. 3395-3397

Author(s):

YASUHIRO ASANO ◽

YUKI SAWA ◽

YUKIO TANAKA

Keyword(s):

Recent Experiment ◽

Josephson Effect ◽

Cooper Pairs ◽

Half Metal ◽

Spin Flip ◽

Π State

Motivated by a recent experiment [R. S. Keizer, et. al., Nature 439, 825 (2006)], we study the Josephson effect in superconductor/diffusive half metal/superconductor junctions. The Josephson π-state is more stable than the 0-junction when the spin-flip scattering at the junction interface opens the Josephson channel of the odd-frequency Cooper pairs.

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A Simple Model for Investigation of the Pair Breaking Effect on the Parameters of HTS/FM Thin Films

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.662 ◽

2015 ◽

Vol 233-234 ◽

pp. 662-665

Author(s):

Timerfayaz Nurgaliev ◽

Ludmila Uspenskaya

Keyword(s):

Thin Films ◽

Simple Model ◽

High Temperature Superconductor ◽

Cooper Pair ◽

Exponential Dependence ◽

Cooper Pairs ◽

Pair Breaking ◽

Breaking Effect ◽

Microwave Surface Impedance ◽

Spin Polarized

A simple model was proposed for description of Cooper pair breaking effect (which is caused by transfer of spin-polarized carriers from the ferromagnetic (FM) manganite into the high temperature superconductor (HTS)) on the critical temperature and the microwave surface impedance of HTS/FM heterostructures. The model is based on the assumption on an exponential dependence of the Cooper pairs concentration (as well as number of the holes in CuO2 planes, responsible for the superconductivity) on the distance from HTS/FM interface. The model fits well the thickness dependence of HTS film parameters and is used for evaluation of the penetration depth of spin-polarized particles into HTS in the HTS/FM structures.

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Long-range supercurrents through a chiral non-collinear antiferromagnet in lateral Josephson junctions

Nature Materials ◽

10.1038/s41563-021-01061-9 ◽

2021 ◽

Author(s):

Kun-Rok Jeon ◽

Binoy Krishna Hazra ◽

Kyungjune Cho ◽

Anirban Chakraborty ◽

Jae-Chun Jeon ◽

...

Keyword(s):

Long Range ◽

Quantum Interference ◽

Berry Phase ◽

Atomic Scale ◽

Cooper Pairs ◽

Pair Correlations ◽

Spin Correlations ◽

Spin Polarized ◽

Phase Engineering ◽

Proximity Coupling

AbstractThe proximity-coupling of a chiral non-collinear antiferromagnet (AFM)1–5 with a singlet superconductor allows spin-unpolarized singlet Cooper pairs to be converted into spin-polarized triplet pairs6–8, thereby enabling non-dissipative, long-range spin correlations9–14. The mechanism of this conversion derives from fictitious magnetic fields that are created by a non-zero Berry phase15 in AFMs with non-collinear atomic-scale spin arrangements1–5. Here we report long-ranged lateral Josephson supercurrents through an epitaxial thin film of the triangular chiral AFM Mn3Ge (refs. 3–5). The Josephson supercurrents in this chiral AFM decay by approximately one to two orders of magnitude slower than would be expected for singlet pair correlations9–14 and their response to an external magnetic field reflects a clear spatial quantum interference. Given the long-range supercurrents present in both single- and mixed-phase Mn3Ge, but absent in a collinear AFM IrMn16, our results pave a way for the topological generation of spin-polarized triplet pairs6–8 via Berry phase engineering15 of the chiral AFMs.

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Structural, electronic and optical properties of the Zn0.5V0.5S in three phases

Modern Physics Letters B ◽

10.1142/s0217984916503565 ◽

2016 ◽

Vol 30 (29) ◽

pp. 1650356

Author(s):

Zhu-Hua Yin ◽

Jian-Min Zhang

Keyword(s):

Optical Properties ◽

First Principles Calculation ◽

Index Formula ◽

Ultraviolet Region ◽

Good Prospect ◽

Electronic And Optical Properties ◽

Half Metal ◽

Ultraviolet Range ◽

Spin Polarized ◽

Trigonal Structure

The structural, electronic and optical properties of the [Formula: see text], [Formula: see text] and [Formula: see text] are studied by the spin-polarized first-principles calculation. The [Formula: see text] and [Formula: see text] are metals in tetragonal structures, while the [Formula: see text] in trigonal structure is half-metal with 100% spin polarization. The [Formula: see text] has the biggest static dielectric constant [Formula: see text] and static refractive index [Formula: see text], which may be ascribed to the highest crystal symmetry. The maximum absorption peaks of the [Formula: see text], [Formula: see text] and [Formula: see text] are located about 44 eV in the ultraviolet region, indicating these materials have good prospect for optoelectronic materials in the ultraviolet range.

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In Search for Novel Sn2Co3S2-based Half-metal Ferromagnets

Zeitschrift für Naturforschung B ◽

10.5560/znb.2014-3203 ◽

2014 ◽

Vol 69 (1) ◽

pp. 55-61 ◽

Cited By ~ 6

Author(s):

Florian Pielnhofer ◽

Amadeus Samuel Tragl ◽

Jan Rothballer ◽

Richard Weihrich

Keyword(s):

Density Functional ◽

Substitution Effects ◽

The Novel ◽

Functional Theory ◽

Half Metallic ◽

Half Metal ◽

Spin Polarized ◽

Densities Of States ◽

Metallic Ferromagnet ◽

The Stability

Substitution effects on magnetism of shandite-type compounds have been studied by density functional theory. The decrease of the Fermi level in the novel half-metallic ferromagnet Sn2Co3S2 to higher maxima of the density of states was modeled for substitutions on the Co site by the 3d metals Fe, Mn and Cr due to a rigid band scheme. Spin-polarized energy hyper surfaces and densities of states are calculated for Sn2Co3S2, and experimentally not yet known Sn2Fe3S2, Sn2Mn3S2 and Sn2Cr3S2 with shandite-type structure. The stability of half-metallic ferromagnetic characteristics, Slater-Pauling behavior, and alternative metastable spin states are discussed.

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