IDF - 20 - 10/06/2013

Um Informativo do Departamento de Física da UFPR


        Femtosecond electron delocalization in Poly(thiophene) probed by Resonant
        Auger Spectroscopy, C. Arantes, B. G. A. L. Borges, B. Beck, G. Araujo, L. S. Roman
        and M. L. M. Rocco, Journal of Physical Chemistry  117, 8208-8213 (2013)
        DOI: 10.1021/jp312660d
        Modification of PEDOT:PSS anode buffer layer with HFA for flexible polymer solar
        cells, N. A. D. Yamamoto, , L. F. Lima, R. E. Perdomo, R. Valaski, V. L. Calil,
        A. G. Macedo, M. Cremona and  L. S. Roman, Chemical Physics Letters, 572, 73 - 77

        Gaseous mixtures in vacuum systems and microfluidics, F. Sharipov,  J. Vac. Sci.
        Technol. A 31, 050806 (2013) Aqui
        End corrections for rarefied gas flows through capillaries of finite length. S. Pantazis,
        D. Valougeorgis and F. Sharipov, Vacuum 97, 26-29 (2013) Aqui

        Benchmark problems for mixtures of rarefied gases. I. Couette flow. F. Sharipov and
        J. L. Strapasson, Phys. Fluids,  25, 027101 (2013) Aqui


        Título: Electronic nematicity and unconventional superconductivity in the iron pnictides
        Palestrante: Rafael Monteiro Fernandes  da University of Minnesota, EUA
        Data: 13/06/2013  15:30 hs Quinta-Feira
        Onde: PE 04
        Five years after their discovery, much of the interest in iron
        pnictide materials remains in understanding not only their
        high-temperature superconducting phase, but also the nature of their
        normal state. In this context, a hotly debated topic is the origin of the
        tetragonal to orthorhombic transition, which either precedes or happens
        simultaneously to a magnetic instability, and persists even in the
        vicinities of the superconducting dome. Experiments have revealed that the
        anisotropies in this orthorhombic phase cannot be explained by the small
        lattice distortion alone, suggesting that the tetragonal symmetry breaking
        is driven by electronic degrees of freedom, dubbed nematic in analogy to
        the physics of liquid crystals. In this talk, I will present a consistent
        microscopic theoretical model for this nematic phase and explore its
        manifestations in a variety of macroscopic properties of the iron
        pnictides ??? such as elastic, magnetic, and transport properties. The model
        is rooted on the degeneracy of the magnetic ground state of these
        materials, which, allied to the coupling to the lattice and to the orbital
        degrees of freedom, leads to a spontaneous tetragonal symmetry breaking in
         paramagnetic phase. I will also discuss the impact of both nematic
        order and nematic fluctuations to the unconventional s+- superconducting
        state of the iron pnictides and, in particular, whether nematicity can
        play a significant role in the search for higher Tc in these materials.



    Teses e Dissertações



        Estão abertas as inscrições até o dia 21 de junho de 2013, para MESTRADO
        e DOUTORADO do Programa de Pós-GraduaçãoAqui

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