  We calculate conductance through a quantum dot weakly coupled to metallic
contacts by means of Keldysh out of equilibrium formalism. We model the quantum
dot with the SU(2) Anderson model and consider the limit of infinite Coulomb
repulsion. We solve the interacting system with the numerical diagrammatic
Non-Crossing Approximation (NCA). We calculate the conductance as a function of
temperature and gate voltage, from differential conductance (dI/dV) curves. We
discuss these results in comparison with those from the linear response
approach which can be performed directly in equilibrium conditions. Comparison
shows that out of equilibrium results are in good agreement with the ones from
linear response supporting reliability to the method employed. The discussion
becomes relevant when dealing with general transport models through interacting
regions. We also analyze the evolution of the curve of conductance vs gate
voltage with temperature. While at high temperatures the conductance is peaked
when the Fermi energy coincides with the energy of the localized level, it
presents a plateau for low temperatures as a consequence of Kondo effect. We
discuss different ways to determine Kondo's temperature and compare the values
obtained in and out of equilibrium.
