Related papers: Transversal flexoelectric coefficient for nanostru…
We develop a general and unified first-principles theory of piezoelectric and flexoelectric tensor, formulated in such a way that the tensor elements can be computed directly in the context of density-functional calculations, including…
Flexoelectricity phenomenon is the response of electric polarization to an applied strain gradient and is developed as a consequence of crystal symmetry in all materials. In this study, we show that the presence of strain gradient in…
Flexoelectricity is a property of all dielectric materials, where inhomogeneous strain induces electrical polarization. This effect becomes particularly prominent at the nanoscale where larger strain gradients can be obtained. While…
A strong coupling between electric polarization and elastic deformation in solids is an important factor in creating useful electromechanical nanodevices. Such coupling is typically allowed in insulating materials with inversion symmetry…
Flexoelectric effect is the coupling between strain, polarization and their gradients, which are prominent at the nanoscale. Although this effect is important to understand nanostructures, such as domain walls in ferroelectrics, its…
Flexoelectricity induced by strain gradient in dielectrics is highly desirable for electromechanical actuating and sensing systems. It is broadly adopted that flexoelectric polarization responds linearly to strain gradient without…
We derive the complete flexoelectric tensor, including electronic and lattice-mediated effects, of an arbitrary insulator in terms of the microscopic linear response of the crystal to atomic displacements. The basic ingredient, which can be…
The flexoelectric and electronic properties of zig-zag graphene nanoribbons are explored under mechanical bending using state of the art first principles calculations. A linear dependence of the bending induced out of plane polarization on…
Nanostructuring materials at small scales enables control over their physical properties, revealing behaviors not observed at larger dimensions. This strategy is particularly effective in two-dimensional (2D) materials, where surface…
We calculated a spin-polarized conductance in the almost unexplored nanostructure "high temperature ferromagnetic insulator/ graphene/ ferroelectric film" with a special attention to the impact of electric polarization rotation in a…
The aim of this Chapter is to provide an account of recent advances in the first-principles modeling of ferroelectric oxide nanostructures. Starting from a microscopic description of ferroelectricity in bulk materials and considering then,…
Flexoelectricity is a universal effect that generates electric polarization due to broken inversion symmetry caused by local strain gradient. The large strain gradient at nanoscale makes flexo-electric effects, especially in nanoscopic…
We theoretically study the electrical, thermal and thermoelectric transport properties of graphene nanoribbons under torsional deformations. The modelling follows a nonequilibrium Green's function approach in the ballistic transport regime,…
Polar chiral structures have recently attracted much interest within the scientific community, as they pave the way towards innovative device concepts similar to the developments achieved in nanomagnetism. Despite the growing interest, many…
The flexoelectric behaviors of solids under high strain gradient can be distinct from that under low strain gradient. Using the generalized Bloch theorem, we investigate theoretically the transversal flexoelectric effects in bent MgO…
The calculation of the polarization in ferroelectric thin films is performed using an analytical solution of the Euler-Lagrange differential equation with boundary conditions with different extrapolation lengths of positive sign on the…
We study the bending of rectangular atomic monolayers along different directions from first principles. Specifically, choosing the phosphorene, GeS, TiS$_3$, and As$_2$S$_3$ monolayers as representative examples, we perform Kohn-Sham…
Nanowires show a large potential for various electrooptical devices, such as light emitting diodes, solar cells and nanowire lasers. We present a direct method developed to calculate the modal reflection and transmission matrix at the end…
We investigate the electromechanical response of doubly clamped graphene nanoribbons to a transverse gate voltage. An analytical model is developed to predict the field-induced deformation of graphene nanoribbons as a function of field…
This work is the first step towards understanding thermionic transport properties of graphene/phosphorene/graphene van der Waals heterostructures in contact with gold electrodes by using density functional theory based first principles…