Theory of structural response to macroscopic electric fields in ferroelectric systems

Details Theory of structural response to macroscopic electric fields in ferroelectric systems Theory of structural response to macroscopic electric fields in ferroelectric systems

2002-05-21

arxiv.org/abs/cond-mat/0205442v1

Phys. Rev. B 66, 104108 (2002)

Physics

Condensed Matter

Materials Science

19 pages, with 15 postscript figures embedded. Uses REVTEX4 and epsf macros. Also available at http://www.physics.rutgers.ed

Scientific paper

10.1103/PhysRevB.66.104108

We have developed and implemented a formalism for computing the structural response of a periodic insulating system to a homogeneous static electric field within density-functional perturbation theory (DFPT). We consider the thermodynamic potentials E(R,eta,e) and F(R,eta,e) whose minimization with respect to the internal structural parameters R and unit cell strain eta yields the equilibrium structure at fixed electric field e and polarization P, respectively. First-order expansion of E(R,eta,e) in e leads to a useful approximation in which R(P) and eta(P) can be obtained by simply minimizing the zero-field internal energy with respect to structural coordinates subject to the constraint of a fixed spontaneous polarization P. To facilitate this minimization, we formulate a modified DFPT scheme such that the computed derivatives of the polarization are consistent with the discretized form of the Berry-phase expression. We then describe the application of this approach to several problems associated with bulk and short-period superlattice structures of ferroelectric materials such as BaTiO3 and PbTiO3. These include the effects of compositionally broken inversion symmetry, the equilibrium structure for high values of polarization, field-induced structural phase transitions, and the lattice contributions to the linear and the non-linear dielectric constants.

Affiliated with

Also associated with

No associations

Rating

Theory of structural response to macroscopic electric fields in ferroelectric systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Theory of structural response to macroscopic electric fields in ferroelectric systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Theory of structural response to macroscopic electric fields in ferroelectric systems will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-454534