Thermal and Electric Properties of the Delafossites: The Apparent Fermi Liquid Scenario and the Extension of the Density Matrix Renormalization Group Method to Finite Temperatures = Propriétés électriques et thermiques des delafossites : Le scénario du liquide de Fermi apparent et l'extension de la méthode DMRG aux températures finies

This work proposes techniques to access physical properties at intermediate temperatures. These methods include both numerical and analytic ones. The former ones operate within the DMRG aiming to characterize a system at finite temperature by a set of states. The latter ones are applied to a density of states believed to describe the delafossites. These materials have revealed a behavior at intermediate temperatures resembling a Fermi liquid one which is examined with the proposed methods.