First temperature corrections to the Fermi-liquid fixed point in two dimensions - art. no. 054414

We calculate, using perturbative calculations and Ward identities, the basi c parameters of the Fermi liquid: the scattering vertex, the Landau interac tion function, the effective mass, specific heat, and physical susceptibili ties for a model of two-dimensional (2D) fermions with a short-ranged inter action at nonzero temperature. The leading temperature dependence of the sp in components of the scattering vertex, the Landau function, and the spin s usceptibility is found to be linear. We find that the standard T=0 relation ships for a Galilean-invariant Fermi liquid are violated by finite-temperat ure terms. The coefficients in the temperature corrections to these relatio nships involve a subtle interplay between contributions from small and larg e (similar to 2k(F)) momentum processes. A connection with previous studies of the 2D Fermi-liquid parameters is discussed. We conclude that the linea r leading temperature dependence of the parameters is a generic feature of the 2D Fermi liquid.