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The bulge in the basal plane area of cuprate superconductors - evidence for 3a singlet hole pairs

Jürgen Röhler
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Abstract

The bulge in the doping dependence of the basal plane area in hole doped cuprate superconductors is connected with a non-double-occupancy constraint for the oxygen cages in the CuO_2 lattice. This constraint favors the formation of 3a hole pairs growing to filaments with gapless excitations along the (pi, pi) direction. Thus in the pseudogap regime a nodal metal of hole pairs is created. Densest packed 3a hole pairs stabilize the optimum doped state at n =1/6 ~ 0.16.

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Jürgen Röhler. 2006-07-19. The bulge in the basal plane area of cuprate superconductors - evidence for 3a singlet hole pairs. https://doi.org/10.1016/j.physc.2007.03.054

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