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MnNb3S6 is a monoaxial chiral magnet and stabilizes magnetic solitons in the presence of a magnetic field (H). The number of solitons can be controlled by varying H. Furthermore, MnNb3S6 exhibits magnetization relaxation due to soliton annihilation, that is, a nonequilibrium chiral soliton lattice (CSL) state. In this study, we observed soliton locking phenomena in a CSL state on bulk MnNb3S6 crystal, as on micro-processed crystals of CrNb3S6. Thus, we could create nonequilibrium and equilibrium CSL states and switch between them. A numerical simulation revealed that the soliton number was preserved in the soliton locking region; thus, magnetization relaxation was not observed. [ABSTRACT FROM AUTHOR]

Hydrogen (H) plays an important role in determining the reliability and performance of HfO2- and Al2O3-based high-k dielectric electronic devices. In order to understand H behavior, deuterium (D), an isotope of H, was introduced into the poly-Si cap of Al2O3/HfxSi1-xO2/SiO2 high-k stacks by ion implantation. Atom probe tomography was used to image the D distribution in samples annealed under different conditions. The results clearly demonstrated that the D atoms were trapped at the interface of poly-Si and Al2O3 after annealing at 900 K for 10 min. Thus, it is possible that Al2O3 blocks the H atoms at the surface, preventing them from diffusing into the high-k dielectrics during the H2 annealing process in current fabrication technology. The current work also exhibits an example of investigating H behavior in semiconductors by atom probe tomography. [ABSTRACT FROM AUTHOR]

An Eu2+-activated AlN phosphor was synthesized by firing the powder mixture of AlN, α-Si3N4, and Eu2O3 at 2050 °C for 4 h under 1.0 MPa N2. This nitride phosphor emits a strong blue color with the chromaticity coordinates of x=0.139 and y=0.106 at an accelerating voltage of 3 kV. The cathodoluminescence properties of AlN:Eu2+ was evaluated by utilizing it in the Spindt-type field emission display panel. It shows that the nitride phosphor exhibits higher brightness, higher color purity, lower saturation, and longer lifetime than the currently used Y2SiO5:Ce3+, indicative of the suitability of the AlN:Eu2+ blue phosphor in field emission displays. [ABSTRACT FROM AUTHOR]

The temperature dependence of magnetocrystalline anisotropy constants and the saturation magnetization in a single variant state have been investigated for L10-type Fe60Pt40 bulk single crystal prepared under compressive stress. The uniaxial magnetocrystalline anisotropy constant Ku evaluated from the magnetization curve is 6.9×107 erg cm-3 at 5 K. The values of the second- and fourth-order magnetocrystalline anisotropy constants K1 and K2 at 5 K determined by the Sucksmith–Thompson method are 7.4 and 0.13×107 erg cm-3, respectively. Both the values of Ku and K1 decrease with increasing temperature T, while K2 is almost independent of T. The difference between the power law of the Callen and Callen model is described by the dimensionality and the thermal variation of the axial ratio c/a due to the thermal expansion. [ABSTRACT FROM AUTHOR]

Examines the strain effects on critical current densities for conductors with stoichiometric Nb[sub 3]Al filaments. Preparation of the filaments by phase transformation; Comparison of strain sensitivity among different conductors; Degradation of critical current densities.

Presents the microstructural characterization of the longitudinal cross section of Nb[sub 3]Al wires fabricated by an Nb tube composite process. Observation of the Al[sub 5] superconducting compound and unreacted fibrous Nb; Average Al concentration at the Al[sub 5] grain.

The Bi-(Pb)-Sr-Ca-Cu-O superconductor was fabricated into tapes with a Cu sheath. Measurements of magnetization and critical current density Jc in magnetic fields up to 23 T were made for them. The magnetization measurement revealed that, at 4.2 K, these tape specimens had excellent Jc -H(magnetic field) characteristics, while at 77 K, the flux pinning force in them was reduced to zero above 0.3 T due to the flux creep. In the resistive Jc measurement at 4.2 K, these tape specimens showed Jc of ∼7000 A/cm2 at 23. The Jc -H curve showed a slight peak effect, indicating the peak over 30 T. [ABSTRACT FROM AUTHOR]

For Nb3Al multifilamentary superconductors fabricated by a newly developed composite process using continuous ultrafine Al-based alloy cores and pure Nb matrix, Jc properties have been investigated in detail in regard to the size and morphology of the Al core. A significant enhancement in pinning force caused by reducing the Al core size and an anisotropy in Jc observed in a rolled tape have indicated that the Nb3Al-matrix (or core) interface acts as a dominant pinning center of fluxoids. [ABSTRACT FROM AUTHOR]

MnNb3S6 is a monoaxial chiral magnet and stabilizes magnetic solitons in the presence of a magnetic field (H). The number of solitons can be controlled by varying H. Furthermore, MnNb3S6 exhibits magnetization relaxation due to soliton annihilation, that is, a nonequilibrium chiral soliton lattice (CSL) state. In this study, we observed soliton locking phenomena in a CSL state on bulk MnNb3S6 crystal, as on micro-processed crystals of CrNb3S6. Thus, we could create nonequilibrium and equilibrium CSL states and switch between them. A numerical simulation revealed that the soliton number was preserved in the soliton locking region; thus, magnetization relaxation was not observed. [ABSTRACT FROM AUTHOR]