Dynamical coupling in Pb(Zr,Ti) O 3 solid solutions from first principles

Jiang

2016

J. Adv. Dielect.

We use the first-principles-based molecular dynamic approach to simulate dipolar dynamics of BaZrO 3 /BaTiO 3 superlattice, and obtain its dielectric response. The dielectric response is decomposed into its compositional, as well as the in-plane and out-of-plane parts, which are then discussed in the context of chemical ordering of Zr/Ti ions. We reveal that, while the in-plane dielectric response of BaZrO 3 /BaTiO 3 superlattice also shows dispersion over probing frequency, it shall not be categorized as relaxor.

Section: Relaxor or Not?mentioning

confidence: 99%

Dielectric response of BaZrO₃/BaTiO₃ superlattice

Jiang

2016

J. Adv. Dielect.

“…Recently the magnetic degree of freedom was also added into the combination of MD technique and effective Hamiltonians to investigate terahertz dynamical properties of multiferroics 43 . Combining MD and effective Hamiltonians has allowed the computation of complex dynamical properties, including dielectric responses 38,39,43,45 , electrocaloric effect [46][47][48] , domain dynamics 49 , the creation of electric field by dynamically altering the magnetic dipolar configurations in ferromagnets 50 , and the investigation of BaTiO 3 thin-film capacitors 51 . Let us now describe in details this combination.…”

Section: Combining Molecular Dynamics and Effective Hamiltoniansmentioning

confidence: 99%

“…On the other hand, the effective-Hamiltonian-based MD method deals with the dynamics of the degrees of freedom directly, employing Newton's equation for the local modes, AFD motions and strains for ferroelectrics 38,39 , and also the Landau-Lifshitz-Gilbert equation for magnetic moments [41][42][43] in multiferroics. This approach was used as early as the end of the 1990s to investigate KNbO 3 perovskites 44 .…”

Section: Combining Molecular Dynamics and Effective Hamiltoniansmentioning

confidence: 99%

“…For instance, one can wonder if this coupling can give rise to additional peaks in Raman spectra or to other unexpected phenomena. An effective-Hamiltonianbased MD approach was further developed and exploited to address this important topic 39,45 . First, the energy terms related to the AFD degree of freedom were incorporated in the MD program.…”

Section: Bilinear Couplingmentioning

confidence: 99%

“…23,27,31 ) or molecular dynamics (MD) simulations (see, e.g., Refs. 38,39 ), to predict material properties. A MC simulation generates configurations of a system with certain probabilities determined by their free energies at certain temperatures.…”

Section: Combining Molecular Dynamics and Effective Hamiltoniansmentioning

confidence: 99%

See 2 more Smart Citations

Terahertz Dielectric Response and Coupled Dynamics of Ferroelectrics and Multiferroics From Effective Hamiltonian Simulations

Weerasinghe

Al-Barakati

et al. 2013

Int. J. Mod. Phys. B

Self Cite

Ferroelectric and multiferroic materials form an important class of functional materials. Over the last twenty years, first-principles-based effective Hamiltonian approaches have been successfully developed to simulate these materials. In recent years, effective Hamiltonian approaches were further combined with molecular dynamics methods to investigate terahertz dynamical properties of various perovskites. With this combination, a variety of ferroelectric and multiferroic materials, including BaTiO3, Ba(Sr,Ti)O3, Pb(Zr,Ti)O3, BiFeO3, and SrTiO3 bulks and films have been simulated, which led to the understanding of complex phenomena and discovery of novel effects. In this review, we first provide technical details about effective Hamiltonians and molecular dynamics simulation. Then, we present applications of the combination of these two techniques to different perovskites. Finally, we also briefly discuss possible future directions of this approach.

Ultrafast Ferroelectric Domain Switching Induced by Nano‐Second Strain‐Pulse

Shi

Cheng

et al. 2021

Advcd Theory and Sims

Ferroelectric materials subjected to ultrafast external stimuli have been demonstrated to exhibit dynamic phenomena with potential applications in the high-speed operation of ferroelectric data-storage devices. A modified phase-field model is developed to investigate the ferroelectric domain evolution for Pb(Zr,Ti)O 3 bulk materials under nano-second strain-pulse stimuli. In contrast to the ultrafast electric field pulses, where the ferroelectric domain is switched through domain-wall motion over the entire duration of the pulses, the nano-second strain-pulse induces ultrafast domain switching at the beginning of the pulse, after which the domain structure of the material remains stable. A tensile strain pulse (10 ns) with a critical magnitude of 4.4% is demonstrated to completely switch c domain to a domain. In addition, c domain can also be fully switched to a domain through multiple-step domain reversals under the periodic small magnitude (2.0%) of strain pulses (5 ns). The theoretical insights obtained in this work are expected to provide useful guidance for exploring and manipulating the ultrafast dynamic functionalities of ferroelectric materials.