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تسجيل مستخدم جديدDensity-functional calculations of the electronic structure and lattice dynamics of superconducting LaO$_{0.5}$F$_{0.5}$BiS$_{2}$: Evidence for an electron-phonon interaction near the charge-density-wave instability
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We discuss the electronic structure, lattice dynamics and electron-phonon interaction of newly discovered superconductor LaO$_{0.5}$F$_{0.5}$BiS$_{2}$ using density functional based calculations. A strong Fermi surface nesting at $mathbf{k}$=($pi $,$pi $,0) suggests a proximity to charge density wave instability and leads to imaginary harmonic phonons at this $mathbf{k}$ point associated with in-plane displacements of S atoms. Total energy analysis resolves only a shallow double-well potential well preventing the appearance of static long-range order. Both harmonic and anharmonic contributions to electron-phonon coupling are evaluated and give a total coupling constant $lambda simeq 0.85$ prompting this material to be a conventional superconductor contrary to structurally similar FeAs materials.
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We report density functional calculations of the electronic structure, Fermi surface, phonon spectrum and electron--phonon coupling for newly discovered superconductor LaO$_{0.5}$F$_{0.5}$BiSe$_{2}$. Significant similarity between LaO$_{0.5}$F$_{0.5}
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