6,397 research outputs found

    Electronic properties of emergent topological defects in chiral pp-wave superconductivity

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    Chiral pp-wave superconductors in applied magnetic field can exhibit more complex topological defects than just conventional superconducting vortices, due to the two-component order parameter (OP) and the broken time-reversal symmetry. We investigate the electronic properties of those exotic states, some of which contain clusters of one-component vortices in chiral components of the OP and/or exhibit skyrmionic character in the \textit{relative} OP space, all obtained as a self-consistent solution of the microscopic Bogoliubov-de Gennes equations. We reveal the link between the local density of states (LDOS) of the novel topological states and the behavior of the chiral domain wall between the OP components, enabling direct identification of those states in scanning tunneling microscopy. For example, a skyrmion always contains a closed chiral domain wall, which is found to be mapped exactly by zero-bias peaks in LDOS. Moreover, the LDOS exhibits electron-hole asymmetry, which is different from the LDOS of conventional vortex states with the same vorticity. Finally, we present the magnetic field and temperature dependence of the properties of a skyrmion, indicating that this topological defect can be surprisingly large in size, and can be pinned by an artificially indented non-superconducting closed path in the sample. These features are expected to facilitate the experimental observation of skyrmionic states, thereby enabling experimental verification of chirality in emerging superconducting materials

    Hyper-chaotic magnetisation dynamics of two interacting dipoles

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    The present work is a numerical study of the deterministic spin dynamics of two interacting anisotropic magnetic particles in the presence of a time-dependent external magnetic field using the Landau–Lifshitz equation. Particles are coupled through the dipole–dipole interaction. The applied magnetic field is made of a constant longitudinal amplitude component and a time-dependent transversal amplitude component. Dynamical states obtained are represented by their Lyapunov exponents and bifurcation diagrams. The dependence on the largest and the second largest Lyapunov exponents, as a function of the magnitude and frequency of the applied magnetic field, and the relative distance between particles, is studied. The system presents multiple transitions between regular and chaotic behaviour depending on the control parameters. In particular, the system presents consistent hyper-chaotic states

    Assessing the Nutrition Knowledge and Body Image Perceptions of Minority Freshman at East Tennessee State University

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    The health status of African American and Hispanic communities is in need of intervention. These minority groups have a health disparity gap from other races. The incidences of hypertension, diabetes, and obesity are greater in the African American and Hispanic communities. There is a need to continue addressing the specific health issues, along with ideas of body perception, plaguing the African American and Hispanic populations in the United States. Such disparities typically include those who follow “western” diets, have a lack of exercise, are predisposed to chronic illness, as well as have a need for continuous education of the subject matter. This research project is addressing the need for nutrition interventions in the Johnson City, Tennessee minority community, specifically the African American and Hispanic populations. Prevention can be a useful tool in the reduction of health disparities. Freshman, minority students represent a suitable population to implement prevention strategies. East Tennessee State University’s Quest Program is designed specifically for freshman, minority students. The focus group of this research project includes the participants of the Quest program at East Tennessee State University (ETSU). The purpose of this research is to determine the degree of nutrition knowledge and to assess perceptions of body image of minority freshman at ETSU

    Correlated photon pairs generated from a warm atomic ensemble

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    We present measurements of the cross-correlation function of photon pairs at 780 nm and 1367 nm, generated in a hot rubidium vapor cell. The temporal character of the biphoton is determined by the dispersive properties of the medium where the pair generation takes place. We show that short correlation times occur for optically thick samples, which can be understood in terms of off-resonant pair generation. By modifying the linear response of the sample, we produce near-resonant photon pairs, which could in principle be used for entanglement distribution

    La Investigación En La Práctica Pedagógica De Los Docentes De Educación Media

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    La investigación docente no debe estar limitada a campos específicos de las universidades, por el contrario, es pertinente que los docentes en todos los niveles educativos del sistema escolar, apoyen su práctica pedagógica con la realización de estudios que sistematicen sus experiencias y contribuyan al campo de la educación. El presente artículo exhibe los desarrollos de la tesis doctoral Aproximación Teórica a la Investigación en la Práctica Pedagógica de los Docentes de Educación Media, para el cual se asume una visión epistemológica constructivista, con metodología hermenéutico dialéctica, bajo el paradigma cualitativo y se sigue el método de la teoría fundamentada para el análisis de datos y la generación teórica. El estudio concluye con la presentación de la aproximación teórica según el constructo emergente que se revela en relación a la investigación en la práctica pedagógica de los docentes de educación media
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