The ladder physics in the Spin Fermion model

Understand

A link is established between the spin-fermion (SF) model of the cuprates and the approach based on the analogy between the physics of doped Mott insulators in two dimensions and the physics of fermionic ladders.

• This enables one to use nonperturbative results derived for fermionic ladders to move beyond the large-N approximation in the SF model.
• It is shown that the paramagnon exchange postulated in the SF model has exactly the right form to facilitate the emergence of the fully gapped d-Mott state in the region of the Brillouin zone at the hot spots of the Fermi surface.
• Hence the SF model provides an adequate description of the pseudogap.