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Crystallography, Cristallographie cristallogenèse, Geology, Géologie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Propriétés thermiques, Thermal properties of condensed matter, Propriétés thermiques des solides cristallins, Thermal properties of crystalline solids, Dilatation thermique ; effet thermomécanique et densité, Thermal expansion; thermomechanical effects and density, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés et matériaux diélectriques, piézoélectriques et ferroélectriques, Dielectrics, piezoelectrics, and ferroelectrics and their properties, Matériaux diélectriques, piézoélectriques, ferroélectriques et antiferroélectriques, Dielectric, piezoelectric, ferroelectric and antiferroelectric materials, Niobates, titanates, tantalates, céramiques pzt, etc, Niobates, titanates, tantalates, pzt ceramics, etc, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de croissance cristalline; physique de la croissance cristalline, Methods of crystal growth; physics of crystal growth, Théorie et modèles de la croissance cristalline; physique de la croissance cristalline, morphologie cristalline et orientation cristalline, Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation, Croissance en solution, Growth from solutions, Croissance cristalline en solution, Crystal growth from solutions, Ferroélectrique, Ferroelectric materials, Material ferroeléctrico, Matériau piézoélectrique, Piezoelectric materials, Monocristal, Monocrystals, Mécanisme croissance, Growth mechanism, Mecanismo crecimiento, Méthode TSSG, TSSG method, Método TSSG, Niobate, Niobates, Point Curie, Curie point, Propriété thermique, Thermal properties, Réseau cubique, Cubic lattices, Réseau quadratique, Tetragonal lattices, Stabilité thermique, Thermal stability, Température transition, Transition temperature, Transition phase, Phase transitions, Transición fase, 6540D, 8110A, 8110D, A2. Top-seeded solution growth, B1. Niobates, B1. Perovskite, and B2. Piezoelectric materials

In this work, a large size lead-free piezoelectric single crystal, (K,Na,Li)(Nb,Ta,Sb)O3 (KNLNTS) with the dimensions of 8.5 × 8.5 × 13.5 mm3 was successfully grown by the top-seeded solution growth method. This KNLNTS single crystal with high compositional homogeneity is in the tetragonal phase at room temperature. The Curie temperature Tc of the tetragonal-cubic phase transition temperature is 210 C. The piezoelectric coefficients and electromechanical coupling factors of the [001]c oriented KNLNTS single crystal are d33=172.55 pC/N, d31 = -71.90 pC/N, k31 =0.327, k33=0.523, and kt=0.541. In addition, the crystal shows good thermal stability so that it can be used for making high temperature electromechanical devices.

Crystallography, Cristallographie cristallogenèse, Geology, Géologie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomènes de conductivité dans les semiconducteurs et les isolants, Conductivity phenomena in semiconductors and insulators, Effets thermoélectriques et thermomagnétiques, Thermoelectric and thermomagnetic effects, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de croissance cristalline; physique de la croissance cristalline, Methods of crystal growth; physics of crystal growth, Théorie et modèles de la croissance cristalline; physique de la croissance cristalline, morphologie cristalline et orientation cristalline, Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation, Croissance en phase fondue; fusion de zone et purification de zone, Growth from melts; zone melting and refining, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Solidification, Compensation, Conduction thermostimulée, Thermostimulated conduction, Conductivité électrique, Electrical conductivity, Croissance cristalline en phase fondue, Crystal growth from melts, Lacune, Vacancies, Mobilité Hall, Hall mobility, Mécanisme croissance, Growth mechanism, Mecanismo crecimiento, Méthode Bridgman, Bridgman method, Niveau défaut, Defect level, Niveau profond, Deep level, Nivel profundo, Niveau énergie profond, Deep energy levels, Propriété électrique, Electrical properties, Propriété électronique, Electronic properties, Propiedad electrónica, Semiconducteur II-VI, II-VI semiconductors, Solidification, 7220P, 8110A, 8110F, 8130F, CdZnTe, A1. Characterization, A1. Defects, A2. Bridgman technique, and B2. Semiconducting II-VI materials

We investigated the distribution of deep-level defects in CdZnTe:In ingots along the growth direction using thermally stimulated current (TSC) spectra. Higher concentration of Te antisite-related deep donors were found in the tail region due to Te enrichment in the melt as solidification proceeded. The compensation between In+cd defects and Cd vacancies results in low concentration of net free electrons. High resistivity with n-type conduction was demonstrated from the I-V analysis. Hall mobility is lower in the tail due to higher concentration of Te antisite-related deep donors.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Approximation liaison forte, Tight binding approximation, Electronique spin, Spintronics, Electrónica de espin, Elément matriciel, Matrix elements, Modèle 1 dimension, One dimensional model, Modelo 1 dimensión, Modèle microscopique, Microscopic model, Modelo microscópico, Quantification, Quantization, Transport polarisé en spin, Spin polarized transport, Piezospintronics, and Spin dependent transport

The theoretical prediction that some materials might develop pure spin currents in response to strain is presented. Such piezo-spintronic effect is studied and shown to be allowed by symmetry in several systems. This mechanism opens up a way to obtain and measure pure spin currents. From a close analogy with the theory of electric polarization and the piezoelectric effect, we show that such piezo-spintronics response can be represented in a geometrical form in terms of spin Berry phases. Additionally, we illustrate the ideas by the use of two toy models that displays a non-trivial piezo-spintronic response and discuss on possible experimental realizations on antiferromagnetic insulators.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Aimantation, Magnetization, Effet Seebeck, Seebeck effect, Effet magnétocalorique, Magnetocaloric effects, Entraînement par phonon, Phonon drag, Injection spin, Spin injection, Matériau ferromagnétique, Ferromagnetic materials, Onde acoustique, Acoustic waves, Pouvoir thermoélectrique, Thermoelectric power, Résonance ferromagnétique, Ferromagnetic resonance, Théorie réponse linéaire, Linear response theory, Teoría repuesta lineal, Pompage de spin, Spin pumping, A. Magnetically ordered materials, C. Thermoelectricity, and D. Magnetocalorics

Spin pumping refers to the spin current injection driven by magnetization dynamics from a ferromagnet into adjacent nonmagnetic conductors. Conventionally, ferromagnetic resonance is used to drive the magnetization dynamics and the spin pumping. Recently a new type of spin pumping driven by acoustic waves, i.e., the acoustic spin pumping, has been reported. We present a linear-response theory of the acoustic spin pumping.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Aimantation, Magnetization, Diffusion spin, Spin diffusion, Difusión spin, Déformation élastique, Elastic deformation, Electronique spin, Spintronics, Electrónica de espin, Interaction spin orbite, Spin-orbit interactions, Moment cinétique, Angular momentum, Onde acoustique surface, Acoustic surface waves, Résonance ferromagnétique, Ferromagnetic resonance, A. Nonmagnetic conductors, D. Spin current, D. Spin-rotation coupling, and D. Surface acoustic waves

The spin-rotation coupling (SRC) is responsible for angular momentum conversion between the electron spin and rotational deformations of elastic media, whereby spin current generation from mechanical motions is theoretically predicted. Here a surface acoustic wave (SAW) is considered as an example of such elastic deformations. We formulate the spin diffusion equation that is extended to include the influence of the SRC, and from the solution we find that larger spin currents can be obtained in materials with longer spin lifetimes. This distinct feature arises from the fact that the present method is of purely mechanical origin, i.e., it relies on neither equilibrium magnetization nor spin-orbit coupling, offering a new route to building the so-called rare-metal-free spintronics devices.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Effet Hall de spin, Spin Hall effect, Equation Dirac, Dirac equation, Interaction spin orbite, Spin-orbit interactions, Rotation, Transition interbande, Interband transitions, Transport polarisé en spin, Spin polarized transport, A. Nonmagnetic conductors, D. Spin current, and D. Spin-orbit coupling

We theoretically investigate mechanical spin current generation via spin-orbit coupling on the basis of the generally covariant Dirac equation. In accelerating systems, the spin-orbit coupling is modified by inertial effects. Due to the augmented coupling, spin current is generated from rigid rotation and vibration. Renormalization of the inertial effects due to the interband mixing is also discussed by using the k p perturbation.

Crystallography, Cristallographie cristallogenèse, Geology, Géologie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Structure et morphologie de couches minces, Thin film structure and morphology, Composition et identification des phases, Composition and phase identification, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Etats électroniques, Electron states, Transitions métal-isolant et autres transitions électroniques, Metal-insulator transitions and other electronic transitions, Structure électronique et propriétés électriques des surfaces, interfaces, couches minces et structures de basse dimensionnalité, Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures, Propriétés électriques de couches minces particulières, Electrical properties of specific thin films, Propriétés et matériaux magnétiques, Magnetic properties and materials, Autres propriétés intrinsèques des matériaux magnétiquement ordonnés, Magnetically ordered materials: other intrinsic properties, Limites de phases magnétiques (incluant les transitions magnétiques, le métamagnétisme, etc.), Magnetic phase boundaries (including magnetic transitions, metamagnetism, etc.), Addition europium, Europium additions, Addition fer, Iron additions, Article synthèse, Reviews, Conductivité électrique, Electrical conductivity, Densité élevée, High density, Densidad elevada, Diffraction RX, XRD, Disruption, Breakdown, Effet Jahn Teller, Jahn-Teller effect, Effet pression, Pressure effects, Enclume diamant, Diamond anvil, Yunque diamante, Etude expérimentale, Experimental study, Halogénure, Halides, Isolant Mott, Mott insulating, Moment cinétique, Angular momentum, Rayonnement synchrotron, Synchrotron radiation, Résistivité électrique, Electric resistivity, Spectre absorption RX, X-ray absorption spectra, Spectrométrie Mössbauer, Moessbauer spectroscopy, Sulfure, Sulfides, Symétrie cristalline, Crystal symmetry, Système électrons fortement corrélés, Strongly correlated electron systems, Transfert charge, Charge transfer, Transferencia carga, Transformation phase, Phase transformations, Transition Mott, Mott transition, Transición Mott, Transition magnétique, Magnetic transitions, Transition métal isolant, Metal-insulator transition, Transition phase, Phase transitions, Transición fase, Transition spin, Spin crossover, Transition électronique, Electronic transition, Transición electrónica, Trempe, Quenching, Valence, 6855N, 7530K, CaFe2O4, Fe3O4, X-ray crystallography, electronic transitions, high pressure, and mott insulators

Electronic/magnetic transitions and their structural consequences in Fe-based Mott insulators in a regime of very high static density are the main issue of this short review paper. The paper focuses on the above-mentioned topics based primarily on our previous and ongoing experimental HP studies employing: (i) diamond anvil cells, (ii) synchrotron X-ray diffraction, (iii) 57Fe Mössbauer spectroscopy, (iv) electrical resistance and (v) X-ray absorption spectroscopy. It is shown that applying pressure to such strongly correlated systems leads to a number of changes; including quenching of the orbital moment, quenching of Jahn-Teller distortion, spin crossover, inter-valence charge transfer, insulator―metal transition, moment collapse and volume collapse. These changes may occur simultaneously or sequentially over a range of pressures. Any of these may be accompanied by or be a consequence of a structural phase transition; namely, a change in crystal symmetry. Analyzing this rich variety of phenomena we show the main scenarios which such strongly correlated systems may undergo on the way to a correlation breakdown (Mott transition). To illustrate these scenarios we present recent results for MFeO3 (M = Fe, Ga, Lu, Eu, Pr) and CaFe2O4 ferric oxides; FeCl2 and Fel2 ferrous halides, and FeCr2S4 sulfide. Fe3O4 is given as an example case for the impact of Mössbauer Spectroscopy on High Pressure Crystallography studies.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés et matériaux magnétiques, Magnetic properties and materials, Autres propriétés intrinsèques des matériaux magnétiquement ordonnés, Magnetically ordered materials: other intrinsic properties, Ondes de spin, Spin waves, Effets magnétomécaniques et magnétoélectriques, magnétostriction, Magnetomechanical and magnetoelectric effects, magnetostriction, Propriétés et matériaux diélectriques, piézoélectriques et ferroélectriques, Dielectrics, piezoelectrics, and ferroelectrics and their properties, Ferroélectricité et antiferroélectricité, Ferroelectricity and antiferroelectricity, Structure des domaines; hystérésis, Domain structure; hysteresis, Bore alliage, Boron alloys, Cobalt alliage, Cobalt alloys, Domaine ferroélectrique, Ferroelectric domain, Dominio ferroeléctrico, Dynamique spin, Spin dynamics, Déformation élastique, Elastic deformation, Effet champ électrique, Electric field effects, Effet magnétoélastique, Magnetoelastic effects, Fer alliage, Iron alloys, Ferroélasticité, Ferroelasticity, Fréquence propre, Eigenfrequency, Matériau ferromagnétique, Ferromagnetic materials, Modulation, Métal transition alliage, Transition element alloys, Onde spin, Spin waves, Structure domaine, Domain structure, Vitesse groupe, Group velocity, Cristal magnonique, Magnonic crystal, A. Ferroelectric, A. Ferromagnetic, D. Magnetoelectric coupling, and D. Magnonics

Spin dynamics controlled by magnetoelastic coupling and applied electric fields might play a vital role in future developments of magnonics, i.e., the exploitation of spin waves for the transmission and processing of information. We have performed broadband spin-wave spectroscopy on a magnetostrictive CoFeB alloy grown on a ferroelectric BaTiO3 substrate causing elastic strain with a quasi-periodic modulation. We find characteristic eigenfrequencies and spin-wave modes with large group velocities and small damping. These results suggest bright perspectives for electric-field control of reprogrammable magnonics.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Cobalt alliage, Cobalt alloys, Effet Nernst, Nernst effect, Effet Seebeck, Seebeck effect, Effet champ magnétique, Magnetic field effects, Matériau ferromagnétique, Ferromagnetic materials, Métal transition alliage, Transition element alloys, Orientation champ, Field orientation, Orientacíon campo, Pouvoir thermoélectrique, Thermoelectric power, Transport polarisé en spin, Spin polarized transport, Variation angulaire, Angular variation, Variación angular, Verre métallique, Metallic glasses, A. Amorphous metallic glass, D. Spin Seebeck effect, D. Thermoelectricity, and D. Thermomagnetism

The anomalous, ordinary, and planar Nernst effects of the ferromagnetic bulk metallic glass Co85Si5 Fe3B3Mo2Ni2 are reported. The contribution of the anomalous Nernst signal when the magnetic field is oriented in the plane of the specimen is shown to be zero; yet there is an odd component to the measured signal that varies along the sample length. Even though all measurements here are made using point contacts, and no spin-sensitive Pt strips are present, the signal has similarities to the spin-Seebeck signal.

Crystallography, Cristallographie cristallogenèse, Geology, Géologie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Structure et morphologie de couches minces, Thin film structure and morphology, Composition et identification des phases, Composition and phase identification, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés optiques, spectroscopie et autres interactions de la matière condensée avec les particules et le rayonnement, Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation, Propriétés optiques des matériaux massifs et des couches minces, Optical properties of bulk materials and thin films, Propriétés optiques des couches minces, Optical properties of specific thin films, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Transformations de phases solide-solide à composition constante: polymorphes, massives, ordre-désordre, Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder, Article synthèse, Reviews, Diffraction RX, XRD, Dimension particule, Particle size, Dépendance pression, Pressure dependence, Effet pression, Pressure effects, Glace, Ice, Génération harmonique 2, Second harmonic generation, Haute pression, High pressure, Longueur cohérence, Coherence length, Propriété optique, Optical properties, Quartz, Transformation phase cristalline, Crystal-phase transformations, Transformation phase, Phase transformations, Transition phase, Phase transitions, Transición fase, 6855N, 8130H, ZnO, high pressure, phase transition, and second harmonic generation

This article reviews the most recent results concerning second harmonic generation (SHG) experiments of non-phase matchable and phase matchable powder samples at high pressures and explains the pressure dependence of the intensity of the SHG signal by correlating it to the ratio between the average coherence length and the average particle size. The examples discussed here include pressure-induced structural changes in quartz, ZnO, ice VII and KIO3. It is shown that the second harmonic generation technique is a unique tool for the detection of pressure-induced structural phase transitions. It is laboratory based and allows fast measurements. It is complementary to X-ray diffraction and provides additional information about the presence of an inversion center for unknown or controversially discussed structures at high pressure.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Dynamique spin, Spin dynamics, Effet Nernst Ettingshausen, Nernst Ettingshausen effect, Efecto Nernst Ettingshausen, Effet Seebeck, Seebeck effect, Fer Yttrium Oxyde Mixte, Iron Yttrium Oxides Mixed, Mixto, Fer, Iron, Grenat fer yttrium, YIG, Injection spin, Spin injection, Matériau ferromagnétique, Ferromagnetic materials, Multicouche, Multilayers, Métal transition, Transition elements, Onde spin, Spin waves, PZT, Phonon acoustique, Acoustical phonons, Traitement thermique, Heat treatments, A. Insulators, A. Magnetically ordered materials, D. Phonons, and D. Spin dynamics

The acoustic spin pumping (ASP) stands for the generation of a spin voltage from sound waves in a ferromagnet/paramagnet junction. In this letter, we propose and demonstrate a method for pure detection of the ASP, which enables the separation of sound-wave-driven spin currents from the spin Seebeck effect due to the heating of a sample caused by a sound-wave injection. Our demonstration using a Pt/YIG/PZT sample shows that the ASP signal in this structure measured by a conventional method is considerably offset by the heating signal and that the pure ASP signal is one order of magnitude greater than that reported in the previous study.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Capteur, Sensors, Conductivité thermique, Thermal conductivity, Dissipation thermique, Thermal dissipation, Disipación térmica, Effet Seebeck, Seebeck effect, Effet redresseur, Rectification, Electronique spin, Spintronics, Electrónica de espin, Hyperfréquence, Microwave radiation, Jonction tunnel, Tunnel junction, Unión túnel, Nanostructure, Nanostructures, Onde spin, Spin waves, Jonction tunnel magnétique, Magnetic tunnel junction, A. Magnetic tunnel junctions, C. Microwave imaging, D. Seebeck effects, and D. Spin caloritronics

Recently, the combination of spintronics and thermo-electricity has emerged as the new field of spin caloritronics. It focuses on the coupling of spin transport with heat dissipation and mechanical excitations in magnetic structures. The search to find applications for this new discipline is underway. Motivated by recently discovered Seebeck rectification (Zhang et al., 2012) in nano-structured magnetic tunnel junctions, we explore the possibility of utilizing spin caloritronics in microwave applications. New horizons emerge by using spin caloritronic microwave sensors made of magnetic tunneling junctions, which may be adapted to existing radar and tomographic microwave imaging approaches as well as the standard antenna design procedure.

Crystallography, Cristallographie cristallogenèse, Geology, Géologie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Etats électroniques, Electron states, Méthodes de calcul de structure électronique, Methods of electronic structure calculations, Structure électronique et propriétés électriques des surfaces, interfaces, couches minces et structures de basse dimensionnalité, Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures, Phénomènes de transport électronique dans les couches minces et les structures de basse dimensionnalité, Electronic transport phenomena in thin films and low-dimensional structures, Article synthèse, Reviews, Constante élasticité, Elastic constants, Dynamique réticulaire, Lattice dynamics, Etude théorique, Theoretical study, Haute pression, High pressure, Interaction échange, Exchange interactions, Méthode fonctionnelle densité, Density functional method, Propriété physique, Physical properties, Transition phase, Phase transitions, Transición fase, 7115M, density functional theory, elastic coefficients, exchange-correlation functional, high pressure, lattice dynamics, and phase transitions

Density functional theory based calculations are commonly employed to complement experimental high pressure research. Here, a brief overview of the underlying theory and available codes is provided, followed by some applications. The influence of the choice of the exchange-correlation functional on predicted structural parameters and physical properties is discussed.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Effet Josephson, Josephson effect, Effet bord, Edge effect, Efecto borde, Effet champ magnétique, Magnetic field effects, Effet dimensionnel, Size effect, Facteur forme, Form factors, Facteur g, g-factor, Hybridation, Hybridization, Hétérostructure, Heterostructures, Moment cinétique, Angular momentum, Méthode analytique, Analytical method, Método analítico, Nanofil, Nanowires, Orientation champ, Field orientation, Orientacíon campo, Puits quantique, Quantum wells, Semiconducteur, Semiconductor materials, Théorie Majorana, Majorana theory, Transfert quantité mouvement, Momentum transfer, Transport polarisé en spin, Spin polarized transport, Transfert de spin, Spin transfer, Transistor à spin, Spin transistor, A. Semiconductors, C. Nanowire quantum well, D. Majorana modes, and D. Spin transistor

We propose the manipulation of Majorana edge states via hybridization and spin currents in a nanowire spin transistor. The spin transistor is based on a heterostructure nanowire comprising of semiconductors with large and small g-factors that form the topological and non-topological regions respectively. The hybridization of bound edge states results in spin currents and 4π-periodic torques, as a function of the relative magnetic field angle - an effect which is dual to the fractional Josephson effect. We establish relation between torques and spin-currents in the non-topological region where the magnetic field is almost zero and spin is conserved along the spin-orbit field direction. The angular momentum transfer could be detected by sensitive magnetic resonance force microscopy techniques.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Propriétés et matériaux magnétiques, Magnetic properties and materials, Effets magnétomécaniques et magnétoélectriques, magnétostriction, Magnetomechanical and magnetoelectric effects, magnetostriction, Actionneur, Actuators, Aimantation, Magnetization, Condition aux limites, Boundary conditions, Energie déformation, Strain energy, Energía deformación, Injection spin, Spin injection, Matériau ferromagnétique, Ferromagnetic materials, Onde magnétoélastique, Magnetoelastic waves, Onde transversale, Transverse wave, Onda transversal, Propagation onde, Wave propagation, Relation dispersion, Dispersion relations, Résonance ferromagnétique, Ferromagnetic resonance, Ultrason, Ultrasonic waves, A. Ferromagnets, D. Magnetoelastic coupling, D. Spin pumping, and D. Ultrasound

We study propagation of ultrasonic waves through a ferromagnetic medium with special attention to the boundary conditions at the interface with an ultrasonic actuator. In analogy to charge and spin transport in conductors, we formulate the energy transport through the system as a scattering problem. We find that the magneto-elastic coupling leads to a non-vanishing magnetic (elastic) energy accompanying the acoustic (spin) waves with a resonantly enhanced effect around the anti-crossing in the dispersion relations. We demonstrate the physics of excitating magnetization dynamics via acoustic waves injected around the ferromagnetic resonance frequency.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Transport électronique, Electronic transport in condensed matter, Phénomène de transport dû au spin polarisé, Spin polarized transport, Aimantation, Magnetization, Effet Hall de spin, Spin Hall effect, Effet magnétoélastique, Magnetoelastic effects, Excitation paramétrique, Parametric excitation, Excitación paramétrica, Instabilité, Instability, Méthode paramétrique, Parametric method, Método paramétrico, Nitrure de calcium, Calcium nitride, Calcio nitruro, Onde spin, Spin waves, Onde élastique, Elastic waves, Ultrason, Ultrasonic waves, D. Instability threshold, D. Magnetoelastic effects, D. Parametric excitation, and D. Spin pumping

Recent experiments demonstrated generation of spin currents by ultrasound. We can understand this acoustically induced spin pumping in terms of the coupling between magnetization and lattice waves. Here we study the parametric excitation of magnetization by longitudinal acoustic waves and calculate the acoustic threshold power. The induced magnetization dynamics can be detected by the spin pumping into an adjacent normal metal that displays the inverse spin Hall effect.

Inorganic chemistry, Chimie minérale, Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés et matériaux magnétiques, Magnetic properties and materials, Domaines magnétiques, courbes d'aimantation et hystérésis, Domain effects, magnetization curves, and hysteresis, Courbes d'aimantation, inversion d'aimantation, hystérésis, effet barkhausen et phénomènes associés, Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects, Résonances et relaxations magnétiques dans l'état condensé, effet mössbauer, Magnetic resonances and relaxations in condensed matter, mössbauer effect, Effet mössbauer; autres spectroscopies par rayons γ, Mössbauer effect; other γ-ray spectroscopy, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Métallurgie des poudres. Matériaux composites, Powder metallurgy. Composite materials, Poudres métalliques, Metal powders, Aimantation saturation, Saturation magnetization, Imanación saturación, Aimantation, Magnetization, Broyeur boulet, Ball mill, Molino bolas, Kugelmuehle, Chrome alliage, Chromium alloys, Contrainte interne, Internal stresses, Diffraction RX, XRD, Effet Mössbauer, Moessbauer effect, Fer alliage, Iron alloys, Microscopie électronique balayage, Scanning electron microscopy, Microstructure, Métal transition alliage, Transition element alloys, Métallurgie poudre, Powder metallurgy, Perméabilité magnétique, Magnetic permeability, Silicium alliage, Silicon alloys, Ball-milling, Fe-Si-Cr, Flake, and Mössbauer

Flake-shaped particles were fabricated from crushing ingots with ball milling method. Scanning electron microscope (SEM), X-ray diffraction (XRD), vibrating samples magnetometer (VSM) and Mössbauer spectroscopy measurements were carried out to characterize the milled powders. The XRD results show that the DO3 ordered phase coexists with α-Fe(Si,Cr) matrix phase. Generally, grain size decreases with milling time, as internal strain increases. The fitting result of the Mössbauer spectra of the as-prepared powders reveals that the DO3 phase always exists, but the percentage of DO3 phase drops from 52% in the starting powder to 25% after 80 h milling. A planar anisotropy of the flake-shaped powders is also demonstrated by the Mössbauer spectra, and found to increase with milling time. The saturation magnetization M5 has a maximum value of 109 emu/g after milling of 8 h, and then remains at a steady value around 104 emu/g. The maximum complex permeability is obtained by 32 h milling.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Supraconductivité, Superconductivity, Propriétés des supraconducteurs de type i et de type ii, Properties of type I and type II superconductors, Structure électronique, Electronic structure, Approximation gradient généralisé, Generalized gradient approximation, Calcium Fer Arséniure Mixte, Calcium Iron Arsenides Mixed, Mixto, Densité état électron, Electronic density of states, Dopage, Doping, Magnétisme, Magnetism, Méthode fonctionnelle densité, Density functional method, Niveau Fermi, Fermi level, Onde densité spin, Spin density waves, Structure bande, Band structure, Supraconductivité, Superconductivity, Surface Fermi, Fermi surface, Supraconducteur à base de fer, Iron based superconductors, A. Superconductors, and D. Electronic states

The electronic structure, magnetism and Fermi surface (FS) nesting of the recently discovered superconductive parent material CaFeAs2 are studied by the first-principles, based on the GGA and GGA+U methods. In the nonmagnetic state, the density of states at the Fermi level are mostly derived from the dxy, dyz and dzx orbits, just like LaOFeAs. The Fermi surfaces consist of four hole like FS sheets around the Γ-point, two electron like sheets near the Brillouin zone corner M-point, and small pockets near X-point. The hole like Fermi surfaces will strongly overlap with the electron like FS sheets, if they are shifted by the q-vector q = (π, π, 0). Such FS nesting will induce the magnetic instability and spin density wave (SDW), which has been confirmed to be more stable than other states by the calculated total energy. The calculated bare susceptibility χ0(q) peaked at M-point, and was obviously suppressed with the electron doping. This explains the emergence of the superconductivity in the electron-doped compound Ca1-xLaxFeAs2, because the electron doping suppressed the SDW and induced the superconductivity.

Crystallography, Cristallographie cristallogenèse, Electronics, Electronique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Supraconductivité, Superconductivity, Propriétés des supraconducteurs de type i et de type ii, Properties of type I and type II superconductors, Structure électronique, Electronic structure, Matériaux supraconducteurs (sauf les composés à haute tc), Superconducting materials (excluding high-tc compounds), Métaux, alliages et composés (a15, 001c15, phases de chevrel, phases de laves, borocarbures, etc.), Metals, alloys and compounds (a15, 001c15, laves phases, chevrel phases, borocarbides, etc.), Appariement, Pairing, Emparejamiento, Approximation densité locale, Local density approximation, Aproximación densidad local, Calcul ab initio, Ab initio calculations, Densité état électron, Electronic density of states, Effet pression, Pressure effects, Fluctuation spin, Spin fluctuations, Germaniure, Germanides, Structure bande, Band structure, Supraconducteur, Superconductors, Surface Fermi, Fermi surface, Théorie BCS, BCS theory, A. Superconductors, and D. Electronic band structure

Band structures of pressure-induced CeNiGe3 and exotic BCS-like YNiGe3 superconductors have been calculated employing the full-potential local-orbital code. Both the local density approximation (LDA) and LDA + U treatment of the exchange-correlation energy were used. The investigations were focused on differences between electronic properties of both compounds. Our results indicate that the Ce-based system exhibit a higher density of states at the Fermi level, dominated by the Ce 4f states, in contrast to its non-f-electron counterpart. The Fermi surface (FS) of each compound originates from three bands and consists of both holelike and electronlike sheets. The specific FS nesting properties of only CeNiGe3 enable an occurrence of spin fluctuations of a helicoidal antiferromagnetic character that may lead to unconventional pairing mechanism in this superconductor. In turn, the topology of the FS in YNiGe3 reveals a possibility of multi-band superconductivity, which can explain the observed anomalous jump at Tc in its specific heat.