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The purpose of the present article is to make a model using analytical equations, based on elasticity theory of continuous media for small deformations, with the aim of completely characterizing the material in their mechanical properties as well as the principal stresses-strains of thin films. The approach differs from the standard literature which usually brings crystal symmetries or is directly concerned with crystalline materials. It is entirely possible to define and to analyze anisotropy in elastic media from first principles in thin films. Therefore, the constitutive relation between strain and stress will be considered orthotropic, obeying the generalized Hooke's law. A new equation for the stress of the film-substrate system is proposed based on Newton's laws and energy conservation. As an application, it use the technique and data developed by Faurie et al (2005) in fiber-textured gold film deposited onto Kapton substrate by combining synchrotron X-Ray diffraction in situ tensile testing. As the gold thin film and substrate are considered transversely isotropic, therefore, is firstly required a texture analysis with the purpose of determining the possible Euler angles ($\phi$) and ($\psi$) for each crystallographic direction that can be used in the model equations. With the data, it is possible to make graphics, $\varepsilon$ (strain) X F, for every force applied to the sample. Comparing the experimental graphs with the theoretical equations it was possible obtained their mechanical properties and the principal stresses-strains of the anisotropic gold thin film. The results are compared with the results of Faurie et al (2005).

Microstripline ferromagnetic resonance technique has been used to study the indirect magnetoelectric coupling occurring in an artificial magnetoelectric heterostructure consisting of a magnetostrictive thin film cemented onto a piezoelectric actuator. Two different modes (sweep-field and sweep-frequency modes) of this technique have been employed to quantitatively probe the indirect magnetoelectric coupling and to observe a voltage induced magnetization rotation (of 90 degree). This latter has been validated by the experimental frequency variation of the uniform mode and by the amplitude of the sweep-frequency spectra., Comment: 4 pages, 4 figures, submitted to Applied Physics Letters