  The formation of domains comprising alternating 'hole rich' and 'hole poor'
ladders recently observed by Scanning Tunneling Microscopy by Kohsaka et al.,
on lightly hole doped cuprates, is interpreted in terms of an attractive
mechanism which favors the presence of doped holes on Cu sites located each on
one side of an oxygen atom. This mechanism leads to a geometrical pattern of
alternating hole-rich and hole-poor ladders with a periodicity equal to 4 times
the lattice spacing in the CuO plane, as observed experimentally. To cite this
article: G. Deutscher, P.-G. de Gennes, C. R. Physique 8 (2007).
