Anisotropic Local Correlations and Dynamics in a Relaxor Ferroelectric

Relaxor ferroelectrics have been a focus of intense attention due to their anomalous dielectric characteristics, diffuse phase transitions, and strong piezoelectricity. Understanding the structure and dynamics of relaxors has been one of the long-standing challenges in solid-state physics, with the current model of polar nanoregions in a non-polar matrix providing only a qualitative description of the relaxor phase transitions. In this paper, we investigate the local structure and dynamics in 75%PbMg$_{1/3}$Nb$_{2/3}$O$_3$-25%PbTiO$_3$ (PMN-PT) using molecular dynamics simulations and the dynamic pair distribution function technique. We show for the first time that relaxor transitions can be described by local order parameters. We find that structurally, the relaxor phase is characterized by the presence of highly anisotropic correlations between the local cation displacements. These correlations resemble the hydrogen bond network in water. Our findings contradict the current polar nanoregion model; instead, we suggest a new model of a homogeneous random network of anisotropically coupled dipoles.Comment: We combine our manuscript and supplementary information in one file. 5 pages and 3 figures in main text. 3 pages and 3 figures in supplementary informatio

Resource-Poor Farmers' Constraints regarding Integrated Soil Fertility and Nutrient Management for Sustainable Crop Production: A farm level study in Bangladesh

Sustainable crop production requires a judicious management of soil resources and of all plant nutrient sources available in a farm or a village. The main focus of the study was to determine the constraints faced by the resource-poor farmers regarding integrated soil fertility and nutrient management for sustainable crop production. Field work was conducted in eight villages of four districts in Bangladesh and data were collected from 92 resource-poor farmers through personal interviews. Four point-summated rating scales were used to determine farmers' constraints while five point Likert-type response scales were used to measure the suggestions provided by them to improve the situations. Findings indicated that most of the farmers confronted high problems regarding soil fertility and nutrient management aspects. The issues mostly confronted were the lack of organizing demonstration plots, inadequate training facilities, lack of availability information sources, financial problems, unavailability and unstable price of chemical fertilizers and shortage of knowledge about the beneficial aspect of using organic manure along with chemical fertilizers for crop production. Develop facilities for easy way of getting agricultural loan prior to crop seasons, strengthen extension activities especially for resource-poor farmers, and ensure the availability of chemical fertilizers during cropping seasons with stable price were the matters mostly suggested by farmers to improve the situations.Crop Production/Industries,

Master formula approach to broken chiral U(3)xU(3) symmetry

The master formula approach to chiral symmetry breaking proposed by Yamagishi and Zahed is extended to the U_R(3)xU_L(3) group, in which effects of the U_A(1) anomaly and the flavor symmetry breaking m_u \not= m_d \not= m_s are properly contained. New identities for the gluon topological susceptibility and pi^0, eta, eta' -> gamma^(*) gamma^(*) decays are derived, which exactly embody the consequence from broken chiral symmetry in QCD without relying on any unphysical limit.Comment: Version to appear in PRD, 25 page

On the accuracy of the numerical integrals of the newmark’s method for computing inelastic seismic response

The paper proposes an algorithm of the numerical integration with the modal analysis for computing inelastic seismic responses, and furthermore, the accuracy of the numerical integration with the Newmark’s =1/4 method that is most popular in the earthquake engineering is discussed by comparing with the response computed by the proposed method

Classification of bi-qutrit positive partial transpose entangled edge states by their ranks

We construct $3\otimes 3$ PPT entangled edge states with maximal ranks, to complete the classification of $3\otimes 3$ PPT entangled edge states by their types. The ranks of the states and their partial transposes are 8 and 6, respectively. These examples also disprove claims in the literature.Comment: correct the title to avoid an acronym, correct few text

Observational Test of Environmental Effects on The Local Group Dwarf Spheroidal Galaxies

In this paper, we examine whether tidal forces exerted by the Galaxy or M31 have an influence on the Local Group dwarf spheroidal galaxies (dSphs) which are their companions. We focus on the surface brightness profiles of the dSphs, especially their core radii because it is suggested based on the numerical simulations that tidal disturbance can make core radii extended. We examine the correlation for the dSphs between the distances from their parent galaxy (the Galaxy or M31) and the compactnesses of their surface brightness profiles by using a parameter ``C'' defined newly in this paper. Consequently, we find no significant correlation. We make some remarks on the origin of this result by considering three possible scenarios; tidal picture, dark matter picture, and heterogeneity of the group of dSphs, each of which has been often discussed to understand fundamental properties and formation processes of dSphs.Comment: 14 pages LaTeX, 2 PostScript figures, to appear in ApJ Letter