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Large momentum-dependence of the main dispersion kink in the high-Tc superconductor Bi2Sr2CaCu2O8+{delta}

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 Added by Nicholas Plumb
 Publication date 2013
  fields Physics
and research's language is English




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Ultrahigh resolution angle-resolved photoemission spectroscopy with low-energy photons is used to study the detailed momentum dependence of the well-known nodal kink dispersion anomaly of Bi2Sr2CaCu2O8+{delta}. We find that the kinks location transitions smoothly from a maximum binding energy of about 65 meV at the node of the d-wave superconducting gap to 55 meV roughly one-third of the way to the antinode. Meanwhile, the self-energy spectrum corresponding to the kink dramatically sharpens and intensifies beyond a critical point in momentum space. We discuss the possible bosonic spectrum in energy and momentum space that can couple to the k-space dispersion of the electronic kinks.



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100 - H. Iwasawa , Y. Aiura , T. Saitoh 2005
We present detailed energy dispersions near the Fermi level on the monolayer perovskite ruthenate Sr2RuO4, determined by high-resolution angle-resolved photoemission spectroscopy. An orbital selectivity of the kink in the dispersion of Sr2RuO4 has been found: A kink for the Ru 4d_xy orbital is clearly observed, but not for the Ru 4d_yz and 4d_zx ones. The result provides insight into the origin of the kink.
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