Publications by Dragan Damjanovic

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The electrical conductivity of SrBi4Ti4O15 (SBT) has been measured under controlled oxygen partial pressure. Both acceptor and donor doping effects were studied using de conductivity and impedance measurements. In addition to the ceramic samples with random grain orientation, grain oriented samples were prepared by hot forging. It has been shown that the conductivity of SBT is electronic p type in air at low temperature and it is n type at high temperature (greater than or equal to 700 degrees) up to 1 atm

The dielectric and piezoelectric response of ferroelectric thin films and ceramics was investigated as a function of the driving field amplitude. Detailed analysis of the amplitude and phase angle of the third harmonic of the dielectric displacement and piezoelectrically induced charge shows that the usual phenomenological approach is inadequate to describe experimentally observed field dependence of the dielectric and piezoelectric response. Qualitatively better agreement with experimental data is obtained

Complex lead-based perovskites with the general formula Pb(Bx'B1-x")O3, represent an important class of antiferroelectrics beyond the prototypical PbZrO3 and NaNbO3. Depending on the combination of B-site species and the degree of cationic ordering, these materials exhibit a wide range of ferroic behaviors, spanning from antiferroelectric to (relaxor) ferroelectric responses. In this study, we investigate (Pb1-xBax)(Yb1/2Nb1/2)O3 polycrystals synthesized via a two-step processing route. Despite displaying a

The processing and characterization of electrical properties of potassium niobate ceramic, KNbO3 (KN) have been studied. The difficulty of obtaining dense samples by conventional methods limits the knowledge on electrical properties of this material. In this paper, a complete route for processing of KN with density over 94% is described. Piezoelectric and dielectric data are presented. It is observed that the major problem concerning the density is related to incorrect stoichiometry, which is believed to be

The solid solution 0.5Ba(Ti0.8Zr0.2)O-3-0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising lead-free piezoelectric material with exceptionally high piezoelectric coefficients. The strong response is related to structural instabilities close to ambient temperature. ...

Strain-field measurements and in situ polarized light microscopy have been used to evidence a hysteretic, irreversible electric-field-induced transition to a quasimonodomain rhombohedral phase in 111-oriented, pseudo-orthorhombic PZN-8PT [0.92Pb(Zn1/3 ...

The direct longitudinal piezoelectric effect (d(33)) in lead zirconate titanate, barium titanate, bismuth titanate and strontium bismuth titanate ceramics was investigated with respect to the dependence on the amplitude of an alternating pressure. At low alternating pressure amplitudes, the behaviour of the piezoelectric charge and the piezoelectric coefficient may be explained in terms of the Rayleigh law originally discovered for magnetization and magnetic permeability in ferromagnetic materials. The char

Piezo- and pyroelectric materials are of interest, for example, for energy harvesting applications, for the development of tactile sensors, as well as neuromorphic computing. This study reports the observation of pyro- and piezoelectricity in thin surface- ...

A uniaxial compressive stress significantly modifies the dielectric and piezoelectric response of Pb(Zr,Ti)O3 (PZT)-based piezoceramics. In soft PZT, the pre-stress decreases both the piezoelectric coefficient and its increment with increasing dynamical stress amplitude. However, an increase of both quantities is shown in hard PZT. Similar effects are observed in the dielectric response. It is proposed that the differences between such behaviors are due to the possibility of domain coalescence in the materi

The main mechanism of properties enhancement in the morphotropic phase boundary region separating tetragonal and rhombohedral phases of Pb(Zr1-xTix)O-3 (PZT) is related to polarization rotation. It is shown here that in proximity of the morphotropic phase ...

The mechanism of the giant unipolar strain recently observed in a lead-free piezoceramic, 0.92(Bi0.5Na0.5)TiO3-0.06BaTiO(3)-0.02(K0.5Na0.5)NbO3 [S.-T. Zhang, A. B. Kounga, E. Aulbach, H. Ehrenberg, and J. Rodel, Appl. Phys. Lett. 91, 112906 (2007) was inve ...

The contribution from the irreversible displacement of non-180 degrees domain walls to the direct longitudinal piezoelectric d(33) coefficient of BaTiO3 and Pb(Zr,Ti)O-3 ceramics was determined quantitatively by using the Rayleigh law. Effects of the crystal structure and microstructure of the ceramics as well as the external d.c. pressure on the domain wall contribution to d(33) were examined. In barium titanate, this domain wall contribution is large (up to 35% of the total d(33), under the experimental c

The contribution of non-180 degrees domain wall displacement to the frequency dependence of the longitudinal piezoelectric coefficient has been determined experimentally in lead zirconate titanate using time-resolved, in situ neutron diffraction. Under sub ...

The pyroelectric coefficients of 0.72Pb(Mg1/3Nb2/3)O-3-0.28PbTiO(3) (PMN-28PT), 0.67Pb(Mg1/3Nb2/3)O-3-0.33PbTiO(3) (PMN-33PT), and 0.92 Pb(Zn1/3Nb2/3)O-3-0.08PbTiO(3) (PZN-8PT) single crystals, oriented and poled along three different crystallographic directions, 001, 011, and 111, have been measured using a dynamic method. The suffix C indicates reference to the prototypic cubic coordinate system. Large coefficients of up to 1070 mu C m(-2) K-1 have been observed for the 111 oriented, r

The interfaces in complex oxides present unique properties exploitable in nanoscale devices. Recent studies on ferroelectric BiFeO3, BaTiO3, and Pb(Zr, Ti) O-3 have revealed an unusually high electric conductivity of the domain walls (DWs), adding another ...

We report Raman spectroscopy in all four phases of a (K0.5+delta Na0.5-delta)NbO3 (delta similar to 0.03) crystal and ((K0.5+delta Na0.5-delta)(1-x)Li-x)NbO3 for x=0.02 and 0.03. The phase transitions in the Li-free crystal are homogeneous and hysteretic, ...

The piezoelectric properties of lead zirconate titanate (PZT) thin ﬁlms deposited on thick silicon substrates and thin silicon membranes were investigated using optical interferometry. The effect of the geometrical constraints and clamping effects on the piezoelectric response is discussed. The study of the dielectric permittivity and the loss as a function of the amplitude of the alternating electric field reveals that extrinsic contributions to the dielectric permittivity become active at large fields. Th

Defect engineering is one of the cornerstones of the modern electronics industry. Almost all electronic devices include materials that have been doped by ion bombardment. For materials where crystallinity is essential, such as ferroelectrics, defect type a ...

The role of Fe as an acceptor and Nb as a donor in 0.94−xTiO3–0.06BaTiO3−x (K0.5Na0.5)NbO3 (100xKNN) (x = 0.02 and 0.03) lead-free piezoceramics was investigated. X-ray diffraction analyses show that all the profiles are best-fitted with a cu ...

Through the use of relations analogous to that of the Rayleigh law, it is demonstrated that the ac electric field dependence of the permittivity of ferroelectric thin films can be described. It is further shown that both reversible and irreversible components of the permittivity decrease linearly with the logarithm of the frequency of the ac field. The results demonstrate that the models describing the interaction of domain walls and randomly distributed pinning centers in magnetic materials can be extended

Dragan Damjanovic

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Electrical conductivity of strontium bismuth titanate under controlled oxygen partial pressure

Contributions to the nonlinear dielectric and piezoelectric response of ferroelectric thin films and ceramics

Temperature-dependent field-induced phase transition behavior in Pb(Yb1/2Nb1/2)O3-based antiferroelectrics

Preparation and characterization of KNbO3 ceramics

Elastic, dielectric, and piezoelectric anomalies and Raman spectroscopy of 0.5Ba(Ti0.8Zr0.2)O3-0.5(Ba0.7Ca0.3)TiO3

Electric-field-induced orthorhombic to rhombohedral phase transition in [111](C)-oriented 0.92Pb(Zn1/3Nb2/3)O-3-0.08PbTiO(3)

The Rayleigh law in piezoelectric ceramics

Pyroelectric Polyelectrolyte Brushes

Effect of Uniaxial Compressive Stress on Dielectric and Piezoelectric Responses in Lead Zirconate Titanate Based Ceramics

Antiferroelectric–ferroelectric phase boundary enhances polarization extension in rhombohedral Pb(Zr,Ti)O3

Origin of the large strain response in (K0.5Na0.5)NbO3-modified (Bi0.5Na0.5)TiO3-BaTiO3 lead-free piezoceramics

Contribution of the irreversible displacement of domain walls to the piezoelectric effect in barium titanate and lead zirconate titanate ceramics

An in situ diffraction study of domain wall motion contributions to the frequency dispersion of the piezoelectric coefficient in lead zirconate titanate

Pyroelectric properties of (1-x)Pb(Mg1/3Nb2/3)O-3-xPbTiO(3) and (1-x)Pb(Zn1/3Nb2/3)O-3-xPbTiO(3) single crystals measured using a dynamic method

Mobile Domain Walls as a Bridge between Nanoscale Conductivity and Macroscopic Electromechanical Response

Raman spectroscopy of (K,Na)NbO3 and (K,Na)(1-x)LixNbO3

Properties of Piezoelectric Pzt Thin Films for Microactuator Applications

Nanoscale Defect Engineering and the Resulting Effects on Domain Wall Dynamics in Ferroelectric Thin Films

Effect of Nb-donor and Fe-acceptor dopants in (Bi1/2Na1/2)TiO3–BaTiO3–(K0.5Na0.5)NbO3 lead-free piezoceramics

Evidence of domain wall contribution to the dielectric permittivity in PZT thin films at sub-switching fields