The intrinsic structural metastability in cuprate high Tc​ materials,
evidenced in a checker-board domain structure of the CuO2​ planes, locally
breaks translational and rotational symmetry. Dynamical charge - deformation
fluctuations of such nano-size unidirectional domains, involving Cu-O-Cu
molecular bonds, result in resonantly fluctuating diamagnetic pairs embedded in
a correlated Fermi liquid. As a consequence, the single-particle spectral
properties acquire simultaneously (i) fermionic low energy Bogoliubov branches
for propagating Cooper pairs and (ii) bosonic localized glassy structures for
tightly bound states of them at high energies. The partial localization of the
single-particle excitations results in a fractionation of the Fermi surface as
the strength of the exchange coupling between itinerant fermions and partially
localized fermion pairs increases upon moving from the nodal to the anti-nodal
point. This is also the reason why, upon hole doping, bound fermion pairs
predominantly accumulate near the anti-nodal points and ultimately condense in
an anisotropic fashion, tracking the gap in the single particle spectrum.Comment: 11 pages 5figure