Cr-doping effect on the orbital fluctuation of heavily doped Nd1-xSrxMnO3 (x ~ 0.625)

We have investigated the Cr-doping effect of Nd0.375Sr0.625MnO3 near the phase boundary between the x2-y2 and 3z2-r2 orbital ordered states, where a ferromagnetic correlation and concomitant large magnetoresistance are observed owing to orbital fluctuation. Cr-doping steeply suppresses the ferromagnetic correlation and magnetoresistance in Nd0.375Sr0.625Mn1-yCryO3 with 0 < y < 0.05, while they reappear in 0.05 < y < 0.10. Such a reentrant behavior implies that a phase boundary is located at y = 0.05, or a phase crossover occurs across y = 0.05.Comment: 3 pages, 3 figures, to be published in Journal of Applied Physic

Multiferroic properties of an \aa kermanite Sr2_2CoSi2_2O7_7 single crystal in high magnetic fields

The magnetic and dielectric properties of \aa kermanite Sr$_2$CoSi$_2$O$_7$ single crystals in high magnetic fields were investigated. We have observed finite induced electric polarization along the c axis in high fields, wherein all Co spins were forcibly aligned to the magnetic field direction. Existence of the induced polarization in the spin-polarized state accompanied with the finite slope in the magnetization curve suggests the possible role of the orbital angular momenta in the excited states as its microscopic origin. The emergence of the field-induced polarization without particular magnetic order can be regarded as the magnetoelectric effects of the second order from the symmetry point of view. A low magnetic field-driven electric polarization flip induced by a rotating field, even at room temperature, has been successfully demonstrated.Comment: 12 pages, 4 figure

Impact of fermentation and incorporation of cashew flour on the micronutrient and macronutrient contents of millet flour sold in the market: case of the city of Yamoussoukro

The weaning period of an infant, which should begin from 7 months, is characterized by the gradual change from a liquid to a solid diet. After 6 months, the nutrients contained in breast milk are no longer sufficient to meet the growing demands of the infant. This is the ideal period for the introduction of a complementary food to make up for any deficiencies. To contribute to this situation, two groups, each consisting of five combinations of millet flour, enriched with cashew flour were formulated. The samples M100A0 (Unenriched millet flour), M92,5A7,5, M85A15, M77, 5A22,5 and M70A30 were enriched with 7.5%, 15%, 22,5% and 30% downgraded cashew flour, respectively. The samples MF100A0 (Unenriched fermented millet flour), MF92, 5A7,5, MF85A15, MF77, 5A22,5 and MF70A30 were constructed in a corresponding manner, the only difference being that the millet flour was fermented. After analyses of the different formulations, the best proportions of proteins were observed in MF70A30, MF77, 5A22, 5 and M70A30, which were 13.13%, 12.25% and 12.25%, respectively. Samples M70A30 and M77,5A22,5 exhibited the best iron contents of 8.44 ppm and 8.12 ppm, respectively. The protein contents of the unfortified samples M100A0 and MF100A0 were 7.53% and 6.13% respectively. Formulations MF70A30, M77,5A2,5 and M70A30 with levels of 1.06 ppm, 0.98 ppm and 0.98 ppm, respectively, gave the best zinc contents. The moisture contents of the formulated samples had minimal changes. They varied between 6.16 ± 0.06% and 7.6 ± 0.99% for unfermented samples, and between 6.35 ± 0.32% and 7.0 ± 0.02% for fermented samples. The humidity values of the two groups of samples were not significantly different at P≤0.05. These low moisture contents in the flours are important for better preservation. At the end of this study, certain formulations were selected because of their good nutritional profile. Thus the formulations M70A30 composed of 70% millet flour and 30% cashew flour and MF70A30 composed of 70% fermented millet flour and 30% cashew flour present the best options and could be used as quality infant flours.&nbsp

Theory of magnetoelectric resonance in two-dimensional S=3/2S=3/2 antiferromagnet Ba2CoGe2O7{\rm Ba_2CoGe_2O_7} via spin-dependent metal-ligand hybridization mechanism

We investigate magnetic excitations in an $S=3/2$ Heisenberg model representing two-dimensional antiferromagnet ${\rm Ba_2CoGe_2O_7}$. In terahertz absorption experiment of the compound, Goldstone mode as well as novel magnetic excitations, conventional magnetic resonance at 2 meV and both electric- and magnetic-active excitation at 4 meV, have been observed. By introducing a hard uniaxial anisotropy term $\Lambda (S^z)^2$, three modes can be explained naturally. We also indicate that, via the spin-dependent metal-ligand hybridization mechanism, the 4 meV excitation is an electric-active mode through the coupling between spin and electric-dipole. Moreover, at 4 meV excitation, an interference between magnetic and electric responses emerges as a cross correlated effect. Such cross correlation effects explain the non-reciprocal linear directional dichroism observed in ${\rm Ba_2CoGe_2O_7}$.Comment: 5 pages, 3 figure

Effects of different needles and substrates on CuInS2 deposited by electrostatic spray deposition

Copper indium disulphide (CuInS2) thin films were deposited using the electrostatic spray deposition method. The effects of applied voltage and solution flow rate on the aerosol cone shape, film composition, surface morphology and current conversion were investigated. The effect of aluminium substrates and transparent fluorine doped tin oxide (SnO2:F) coated glass substrates on the properties of as-deposited CuInS2 films were analysed. An oxidation process occurs during the deposition onto the metallic substrates which forms an insulating layer between the photoactive film and substrate. The effects of two different spray needles on the properties of the as-deposited films were also studied. The results reveal that the use of a stainless steel needle results in contamination of the film due to the transfer of metal impurities through the spray whilst this is not seen for the glass needle. The films were characterised using a number of different analytical techniques such as X-ray diffraction, scanning electron microscopy, Rutherford back-scattering and secondary ion mass spectroscopy and opto-electronic measurements

One-Third Magnetization Plateau with a Preceding Novel Phase in Volborthite

We have synthesized high-quality single crystals of volborthite, a seemingly distorted kagome antiferromagnet, and carried out high-field magnetization measurements up to 74 T and 51V NMR measurements up to 30 T. An extremely wide 1/3 magnetization plateau appears above 28 T and continues over 74 T at 1.4 K, which has not been observed in previous study using polycrystalline samples. NMR spectra reveal an incommensurate order (most likely a spin-density wave order) below 22 T and a simple spin structure in the plateau phase. Moreover, a novel intermediate phase is found between 23 and 26 T, where the magnetization varies linearly with magnetic field and the NMR spectra indicate an inhomogeneous distribution of the internal magnetic field. This sequence of phases in volborthite bear a striking similarity to those of frustrated spin chains with a ferromagnetic nearest-neighbor coupling J1 competing with an antiferromagnetic next-nearest-neighbor coupling J2.Comment: 12 pages, 5 figure

Solving integral equations in η→3π\eta\to 3\pi

A dispersive analysis of $\eta\to 3\pi$ decays has been performed in the past by many authors. The numerical analysis of the pertinent integral equations is hampered by two technical difficulties: i) The angular averages of the amplitudes need to be performed along a complicated path in the complex plane. ii) The averaged amplitudes develop singularities along the path of integration in the dispersive representation of the full amplitudes. It is a delicate affair to handle these singularities properly, and independent checks of the obtained solutions are demanding and time consuming. In the present article, we propose a solution method that avoids these difficulties. It is based on a simple deformation of the path of integration in the dispersive representation (not in the angular average). Numerical solutions are then obtained rather straightforwardly. We expect that the method also works for $\omega\to 3\pi$.Comment: 11 pages, 10 Figures. Version accepted for publication in EPJC. The ancillary files contain an updated set of fundamental solutions. The numerical differences to the former set are tiny, see the READMEv2 file for detail