Mean-field & decoupling

Mean-field theory

Decoupling interactions into a self-consistent background field; the first window onto broken symmetry.

Every topic that uses this method, drawn from across all subjects.

• Weak Coupling: Mean-Field Theory and the Slater Insulator Mott Physics in Correlated Lattices Starting from the non-interacting limit, a mean-field decoupling of the Hubbard interaction with staggered magnetization gives an antiferromagnetic two-band insulator. Solving the self-consistent gap equation reveals a Slater gap that opens exponentially at weak coupling and crosses over to the Mott gap Δ → U/2 at strong coupling.