Dynamical magnetic susceptibility in the spin-fermion model for cuprate superconductors (Q1709388)

In the \(\mathrm{SU}(2)\)-invariant spin-fermion model of the copper oxides \(\mathrm{CuO}_2\), the authors obtain the dynamical magnetic susceptibility of the localized \(\mathrm{Cu}\) subsystem with the oxygen holes. To this end, they use the method of diagram techniques for the spin and fermion operators, and calculate the one-loop contribution to the Dyson mass operator in the Matsubara Green's function of the localized spins of the \(\mathrm{Cu}\) subsystem under some approximations. They take the spin-polaron nature of the Fermi quasiparticles into account, and find out that the structure of the Matsubara spin Green's function agrees with that previously obtained by Shimahara and Takada.