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Fermi-surface induced modulation in an optimally doped YBCO superconductor

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 Added by Zahirul Islam
 Publication date 2008
  fields Physics
and research's language is English




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We have observed a Fermi-surface (FS) induced lattice modulation in a YBCO superconductor with a wavevector along CuO chains, {it i.e.} ${bf q}_1$=(0,$delta$,0). The value of $deltasim0.21$ is twice the Fermi wavevector ($2{bf k}_F$) along {bf b*} connecting nearly nested FS `ridges. The ${bf q}_1$ modulation exists only within O-vacancy-ordered islands (characterized by ${bf q}_0$=$(frac14,0,0))$ and persists well above and below $T_c$. Our results are consistent with the presence of a FS-induced charge-density wave.



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