and multiferroic [ 2 ] materials. For instance, ferroelectric materials at morphotropic phase boundaries (MPB), where multiple structural phases with ferroelectric polarizations pointing in different crystallographic directions coexist, often display large piezoelectric coeffi cients. [ 3– 5 ] It is the ferroelectric distortions, which accompany the polarization rotation that leads to enhanceme...

Ferroelectric materials are of growing interest in international research and development. Special attention is drawn to the integration of ferroelectric materials in non-volatile random access memory cells (FeRAMs). For future high-density FeRAMs, the scaling of the size of ferroelectric structures needs to be understood in order to elucidate possible limitations to memory densities. Various e...

Science and technology in the electronics area have always been driven by the development of materials with unique properties and their integration into novel device concepts with the ultimate goal to enable new functionalities in innovative circuit architectures. In particular, a shift in paradigm requires a synergistic approach that combines materials, devices and circuit aspects simultaneous...

Perovskite ferroelectric materials exhibit the novel ferroelectric photovoltaic effect, where photon-excited electron–hole pairs can be separated by ferroelectric polarization. Especially, semiconducting ferroelectric materials with small band gaps ( ) Eg have been extensively studied for applications in solar energy conversion. Traditional route for creating semiconducting ferroelectrics requi...

Using a Ginzburg–Landau–Devonshire type model, the pyroelectric property and hysteresis loop are studied for a composite ferroelectric thin film that contains an insertion of a different type of ferroelectric material in parallel connection with the host ferroelectric film material. If these two types of ferroelectric materials are polarized along the same direction, there are two peaks occur i...

The application of first-principles computational methods to the study of ferroelectric perovskites has greatly expanded our theoretical understanding of this important class of materials. These methods have most recently been applied to an increasingly wide range of ferroelectric materials, with special attention to their lattice dynamics, phase transitions, and dielectric and piezoelectric pr...

We use a first-principles rational-design approach to identify a previously unrecognized class of ferroelectric materials in the P6(3)mc LiGaGe structure type. We calculate structural parameters, polarization, and ferroelectric well depths both for reported and as-yet hypothetical representatives of this class. Our results provide guidance for the experimental realization and further investigat...

Recent work on using atomic-level simulation methods to study the ferroelectric properties of oxide materials is reviewed. In particular, it is illustrated how such methods can provide insights into the physical properties of a wide range of ferroelectric oxide materials inaccessible by other means. Approaches for further improvements in materials fidelity and increased range of applicability a...

The present paper reviews models of domain structure in ferroelectric crystals, thin films and bulk materials. Common crystal structures in ferroelectric materials are described and the theory of compatible domain patterns is introduced. Applications to multi-rank laminates are presented. Alternative models employing phase-field and related techniques are reviewed. The paper then presents metho...