Phenomenological approach of the thermodynamic properties of the charge density wave systems

The properties of the specific heat and elastic stiffness components at the charge density wave phase transition in several one-dimensional and two-dimensional materials are examined. Here we show that the thermodynamic properties of the rare earth tritelluride RTe3 (R=Te, Er) and Lu5Ir4Si10 compounds can be explained in the framework of a standard mean field Landau theory. The amplitude of the experimental-specific heat jump measured at the charge density wave (CDW) phase transition increases with the transition temperature TCDW. The amplitude of the experimental discontinuity of the longitudinal elastic constants measured at the CDW phase transition scales onto a single curve. The Landau approach is discussed as well as experimental results.