Electrically driven ferroelastic domain walls, domain wall interactions, and moving needle domains

Surface Structure of Ferroelastic Domain Walls: a Continuum Elasticity Approach Surface Structure of Ferroelastic Domain Walls: a Continuum Elasticity Approach

We present a model based on continuum elasticity and energy minimization for the study of ferroelastic domain walls close to a surface. We focus on walls orthogonal to the surface, and predict a double-peak structure in the surface values of the squared elastic strain, which is directly related to the chemical reactivity. We also compute the height proole, which can be measured, in principle, e...

Mobility of Domain Walls in Proper Ferroelastic Martensites

Based on the Landau-Ginzberg free energy functional for an Oh-D4h proper ferroelastic martensitic transformation the mobility of a (I 10) twin boundary in a large bicrystal has been calculated by including dissipation in the approximation of the phonon viscosity model and by solving the inverse boundary value problem for the limiting case of strong shear modulus softening. Application to actual...

Asymmetric Response of Ferroelastic Domain-Wall Motion under Applied Bias.

The switching of domains in ferroelectric and multiferroic materials plays a central role in their application to next-generation computer systems, sensing applications, and memory storage. A detailed understanding of the response to electric fields and the switching behavior in the presence of complex domain structures and extrinsic effects (e.g., defects and dislocations) is crucial for the d...

A Domain Wall Model for Hysteresis in Ferroelastic Materials

We develop a model that quantifies constitutive nonlinearities and hysteresis inherent to ferroelastic compounds, with emphasis placed on shape memory alloys. We formulate the model in two steps. First, we use the Landau theory of phase transitions to characterize the effective Gibbs free energy for both single-crystal and polycrystalline ferroelastics. The resulting nonlinear equations model e...

Simulations of Field Driven Domain Wall Interactions in Ferromagnetic Nanowires