Publications by Dragan Damjanovic

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PbTiO3 thin films were prepared from alkoxide solution precursors and crystallized onto Pt/TiO2/SiO2/Si substrates. Microscopy observations revealed that the complexity of the domain walls structure decreased with the grain size. Dielectric, electrostrictive, and piezoelectric properties of the films were characterized in details. A shift of the temperature of the dielectric permittivity maximum due to stresses in the plane of films has been observed. Electrostrictive M and Q coefficients were estimated by

The orientation dependence of the longitudinal piezoelectric coefficient, d(33)(), is investigated as a function of temperature in BaTiO3 and PbTiO3 crystals using the Landau-Ginsburg-Devonshire theory. We show that a presence of the ferroelectric-ferroelectric phase transitions in BaTiO3 leads to enhanced d(33)() along nonpolar directions. The reason for this is that in the vicinity of a phase transition temperature at which a polarization vector changes its direction (tetragonal-orthorhombic/monoclinic,

Piezoelectric actuators (PEAs) have been widely used in nano-positioning applications for their high resolution of displacement. However, hysteresis, which is an inherent property of ferroelectric PEAs has been shown to significantly degrade the system per ...

A large body of work has been reported in the last 5 years on the development of lead-free piezoceramics in the quest to replace lead–zirconate–titanate (PZT) as the main material for electromechanical devices such as actuators, sensors, and transducers. I ...

In ferroelectric materials, domain wall displacement plays a key role in the dielectric properties measured with respect to the driving field amplitude and frequency. The low to medium field dielectric response in many ferroic systems can be often described by classical Rayleigh model, which is rate-independent i.e., it depends only on the strength of ac signal. However experiments show that the nonlinear parameters are frequency dependent. Thus a more general approach, which can describe both purely nonlin

Infrared (IR) reflectivity spectra of nominally pure Pb(Zr1-xTix)O-3 ceramics with different Ti/Zr concentration (x = 0.42-0.58) were measured and evaluated, along with the time-domain terahertz transmittance spectra in the temperature range 10 K-900 K. Th ...

PbTiO3-based ferroelectric solid-solution ceramics have been widely used for electromechanical devices. However, it is still challenging to separate and control the contributions to the electromechanical functionalities, mainly as a function of temperature ...

Ferroelectric orthorhombic lead metaniobate (PbNb2O6) is known to be metastable with respect to the thermodynamically stable nonferroelectric rhombohedral polymorph. The high-temperature tetragonal to low temperature rhombohedral phase transition is recons ...

An evidence that the dielectric aging in the polydomain Pb(Zr0.45Ti0.55)O-3 thin films is controlled by progressive pinning of 180 degrees domain walls is presented. To provide such a conclusion, we use a general method, which is based on the study of the ...

In contrast to usual assumptions, it is shown that even when ferroelastic domain walls are inactive or absent, the motion of ferroelectrically active interfaces in ferroelectric materials contributes, at subcoercive electric fields, not only to the polariz ...

Donor doping is commonly applied for softening of the piezoelectric and dielectric properties and facilitation of polarization switching in the ubiquitous Pb(Zr,Ti)O-3 [PZT] ceramics. The origin of the donor-dopant effects is not entirely clear. (Pb,Ba)ZrO ...

The dielectric response in Bi4Ti3O12 single crystals was studied at subswitching conditions at relative low temperatures (20-250 degrees C) and frequencies (100 mHz to 10kHz) both in-plane and out-of-plane. Electron-holes are likely to be the major charge ...

The piezoelectric properties of tetragonal BaTiO3 (BTO) crystals with a high density of 90° twin domain boundaries were experimentally investigated by Wada and Tsurumi (2004 Br. Ceram. Trans. 103 93). These crystals with engineered dense domain structures exhibit significantly larger intrinsic d33 and d31 coefficients than in mono-domain crystals. This phenomena was studied theoretically and several enhancement mechanisms (domain wall broadening, polarization tilting) were suggested in the past, but no sati

Pb(Zr,Ti)O3 ceramics with homogenous, anisotropic porosity were manufactured and the influence of the anisotropic porosity on the dielectric and piezoelectric properties was studied. Image analysis allowed the quantification of the preferential orientation ...

The dielectric, electrical and structural properties of (1-x) (0.94Bi(1/2)Na(1/2)TiO(3)-0.06BaTiO(3))-xK(0.5)Na(0.5)NbO(3) (BNT-BT-xKNN) with x=0.09, 0.12, 0.15, and 0.18 were investigated as potential candidates for high-temperature capacitors with a working temperature far beyond 200 degrees C. Temperature dependent dielectric permittivity (epsilon) showed two local broad maxima that at the optimal composition of KNN (x=0.18) are combined to form a plateau. This then results in a highly temperature-insens

Many ferroelectric solid solutions exhibit enhanced electromechanical properties at the morphotropic boundary separating two phases with different orientations of polarization. The mechanism of properties enhancement is associated with easy paths for polar ...

It was noticed long time ago that the dielectric permittivity of BaTiO3 single crystals in the rhombohedral phase varies from observation to observation, but the microstructure mechanism behind this phenomenon remained unclear. We show that the variations in susceptibility can be related to the variable domain structure introduced by different pre-treatments at higher temperatures: Electrical depoling at room temperature leads to nano-sized domains and ultrahigh susceptibility in rhombohedral phase, whereas

This article reviews recent advances in the studies of the piezoelectric properties of perovskite materials. Perovskite compositions are the best known and the largest family of ferroelectric and piezoelectric materials.: The dependence of the longitudinal, d(33), piezoelectric:coefficient on crystallographic orientation was examined in single crystals of BaTiO3, PbTiO3, Pb(Zr,Ti)O-3, KNbO3, relaxor-ferroelectric solid solutions [e.g. Pb(Mg1/3Nb2/3)O-3-PbTiO3 and Pb(Zn1/3Nb2/3)O-3-PbTiO3] and Na1/2Bi1/2TiO3

Despite the technological importance of hard and soft PZT, Pb(Zr,Ti)O3, ceramics, the mechanisms of ferroelectric hardening and softening remain widely discussed in the literature. The hardening and softening phenomena have traditionally been investigated ...

Nanocomposites based on polyvinylidene fluoride– trifluoroethylene copolymer and up to 4 vol % of hydrophobized clay nanoparticles are investigated. The structure, piezoelectric properties, and oxygen permeability of solvent cast films are analyzed before ...

Dragan Damjanovic

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Properties of ferroelectric PbTiO3 thin films

Piezoelectric anisotropy-phase transition relations in perovskite single crystals

Quasi-Rayleigh model for modeling hysteresis of piezoelectric actuators

Perspective on the Development of Lead-free Piezoceramics

Analysis of the non linear domain wall response in ferroelectric thin films

Polar lattice vibrations and phase transition dynamics in Pb(Zr1-xTix)O-3

Polar orientation and extension in a novel crystallographic model for PbTiO3-based perovskites explaining the experimental ferroelectric thermal anomalies

Solid Solutions of Lead Metaniobate-Stabilization of the Ferroelectric Polymorph and the Effect on the Lattice Parameters, Dielectric, Ferroelectric, and Piezoelectric Properties

Evidence for dielectric aging due to progressive 180 degrees domain wall pinning in polydomain Pb(Zr0.45Ti0.55)O-3 thin films

Strain-modulated piezoelectric and electrostrictive nonlinearity in ferroelectric thin films without active ferroelastic domain walls

Piezoelectric softening by Nb substitution in (Ba,Pb)ZrO

Conductivity and Ferroelectric Hysteresis in Bi4Ti3O12 Single Crystals Around Room Temperature

The stress-assisted enhancement of piezoelectric properties due to mechanically incompatible domain structures in BaTiO3

Dielectric and piezoelectric properties of PZT ceramics with anisotropic porosity

Lead-free high-temperature dielectrics with wide operational range

A morphotropic phase boundary system based on polarization rotation and polarization extension

Unusual dielectric behavior and domain structure in rhombohedral phase of BaTiO3 single crystals

Piezoelectric properties of perovskite ferroelectrics: Unsolved problems and future research

In-situ structural investigations of ferroelasticity in soft and hard rhombohedral and tetragonal PZT

High diffusion barrier and piezoelectric nanocomposites based on polyvinylidene fluoride-trifluoroethylene copolymer and hydrophobized clay