E. V. L. de Mello

Numerical Study of the Cahn-Hilliard Equation in One, Two and Three Dimensions

The Cahn–Hilliard (CH) equation is related with a number of interesting physical phenomena like the spinodal decomposition, phase separation and phase ordering dynamics. On the other hand this equation is very stiff and the difficulty to solve it numerically increases with the dimensionality and therefore, there are several published numerical studies in one dimension (1D), dealing with different approaches, and much fewer in two dimensions (2D). In three dimensions (3D) there are very few publications, usually concentrate in some specific result without the details of the used numerical scheme. We present here a stable and fast conservative finite difference scheme to solve the CH with two improvements: a splitting potential into an implicit and explicit in time part and the use of free boundary conditions. We show that gradient stability is achieved in one, two and three dimensions with large time marching steps than normal methods.

Resistivity study of the pseudogap phase for (Hg,Re)-1223 superconductors

The pseudogap phase above the critical temperature of high

DYNAMICAL PROPERTIES OF SMALL POLARONS

T_{c}

A Theory for High-

superconductors (HTSC) presents different energy scales and it is currently a matter of intense study. The complexity of the HTSC normal state requires very accurate measurements with the purpose of distinguishing different types of phenomena. Here we have performed systematically studies through electrical resistivity (

T_c

\rho

Superconductors Considering Inhomogeneous Charge Distribution

) measurements by several different current densities in order to obtain an optimal current for each sample. This approach allows to determine reliable values of the pseudogap temperature

Effects of phase separation in the cuprate superconductors

T^{*}(n)

Pressure studies on the pseudogap and critical temperatures of a high-Tc superconductor

, the layer coupling temperature between the superconductor layers

Description and connection between the oxygen order evolution and the superconducting transition in La2CuO4+y

T_{LD}(n)

Electronic phase separation transition as the origin of the superconductivity and pseudogap phase of cuprates

, the fluctuation temperature