Current-density implementation for calculating flexoelectric coefficients

Abstract

The flexoelectric effect refers to polarization induced in an insulator when a strain gradient is applied. We have developed a first-principles methodology based on density-functional perturbation theory to calculate the elements of the bulk, clamped-ion flexoelectric tensor. In order to determine the transverse and shear components directly from a unit cell calculation, we calculate the current density induced by the adiabatic atomic displacements of a long-wavelength acoustic phonon. Previous implementations based on the charge-density response required supercells to capture these components. Our density-functional-theory implementation requires the development of an expression for the current density that is valid for the case of nonlocal pseudopotentials, and long-wavelength phonon perturbations. We benchmark our methodology on simple systems of isolated noble gas atoms, and apply it to calculate the clamped-ion flexoelectric constants for a variety of technologically important cubic oxides. We also discuss some technical issues that are associated with the definition of current density in a nonlocal pseudopotential context, and their relevance to the calculation of macroscopic response properties of crystals.

arXiv comment23 pages, 3 figures

References in corpus (19)

• Phonons and related properties of extended systems from density-functional perturbation theory
• Optimized norm-conserving Vanderbilt pseudopotentials
• All-electron magnetic response with pseudopotentials: NMR chemical shifts
• Giant Flexoelectric Effect in Ferroelectric Epitaxial Thin Films
• Ab-initio theory of NMR chemical shifts in solids and liquids
• Strain Gradients in Epitaxial Ferroelectrics
• First-principles theory and calculation of flexoelectricity
• Orbital magnetoelectric coupling in band insulators
• First principles theory of the EPR g-tensor in solids: defects in quartz
• First-principles theory of frozen-ion flexoelectricity
• Flexoelectricity from density-functional perturbation theory
• Interfacial Polarization and Pyroelectricity in Antiferrodistortive Structures Induced by a Flexoelectric Effect and Rotostriction
• Understanding the origins of the intrinsic dead-layer effect in nanocapacitors
• Surface control of flexoelectricity
• Magnetic susceptibility of insulators from first principles
• Bichiral structure of feroelectric domain wall driven by flexoelectricity
• Coupling of Nonlocal Potentials to Electromagnetic Fields
• Nonlocal pseudopotentials and magnetic fields
• Flexoelectricity induced increase of critical thickness in epitaxial ferroelectric thin films

Cited by in corpus (27)

• A 2D ferroelectric vortex lattice in twisted BaTiO3 freestanding layers
• Does Flexoelectricity Drive Triboelectricity?
• Piezoelectric Electron-Phonon Interaction from Ab Initio Dynamical Quadrupoles: Impact on Charge Transport in Wurtzite GaN
• Flexoelectricity in soft elastomers and the molecular mechanisms underpinning the design and emergence of giant flexoelectricity
• Long-range quadrupole electron-phonon interaction from first principles
• First-principles theory of spatial dispersion: Dynamical quadrupoles and flexoelectricity
• Direct and converse flexoelectricity in two-dimensional materials
• Switching a polar metal via strain gradients
• Transversal flexoelectric coefficient for nanostructures at finite deformations from first principles
• Perspective: strain and strain gradient engineering in membranes of quantum materials
• Phonon-limited Mobility of 2D Semiconductors: Quadrupole Scattering and Free-carrier Screening
• On the role of flexoelectricity in triboelectricity for randomly rough surfaces
• Nonadiabatic Born effective charges in metals and the Drude weight
• Using high multipolar orders to reconstruct the sound velocity in piezoelectrics from lattice dynamics
• Metric-wave approach to flexoelectricity within density-functional perturbation theory
• Quantum theory of mechanical deformations
• Flexoelectric radial polarization of single-walled nanotubes from first-principles
• Lattice-mediated bulk flexoelectricity from first principles
• Rotational $g$ factors and Lorentz forces of molecules and solids from density-functional perturbation theory
• Flexo-Sensitive Polarization Vortices in Thin Ferroelectric Films
• Twin Boundary Mediated Flexoelectricity in LaAlO${}_3$
• Are current discontinuities in molecular devices experimentally observable?
• High-frequency electromagnetic emission from non-local wavefunctions
• Electrically tunable stacking domains and ferroelectricity in moiré superlattices
• Rototranslational sum rules for nuclear dynamics via traveling pseudopotentials
• Symmetry of flexoelectric response in ferroics
• Transversal flexoelectric coefficients for fifty select atomic monolayers from first principles