Pyroelectric properties of polydomain epitaxial Pb(Zr1−x,Tix)

J. Karthik

¹

,

Lane W. Martin

²

Abstract

The pyroelectric properties of polydomain epitaxial Pb(Zr 1-x ,Ti x )O 3 thin films are investigated using a Ginzburg-Landau-Devonshire thermodynamic model. We explore the three major contributions to pyroelectric response in thin films including intrinsic effects and previously neglected contributions such as extrinsic and secondary effects, to provide a complete picture of pyroelectric property development. The pyroelectric coefficient for epitaxial thin films is calculated as a function of strain, temperature, and composition for 0.5 ≤ x ≤ 1.0. We find that structural transitions driven by epitaxial strain can greatly enhance the pyroelectric coefficient and that extrinsic contributions due to temperature driven domain wall motion can significantly alter the intrinsic pyroelectric properties. Furthermore, we show that the pyroelectric coefficient at room temperature is maximized at the multicritical point between various polydomain phases and is also consistently high along the boundary between the c/ a/ c/ a and a 1 / a 2 / a 1 / a 2 polydomain phases. Additionally, we have investigated the impact of epitaxial strain on pyroelectric response in polydomain states and found that the extrinsic contribution from domain walls to the pyroelectric coefficient varies depending on the sign of the strain. Finally we examine the addition of secondary contributions to pyroelectricity that arise from thermal expansion in materials and provide insight into the effect of this contribution on the overall magnitude of response.2

Tuning of dielectric, pyroelectric and ferroelectric properties of 0.715Bi0.5Na0.5TiO3-0.065BaTiO3-0.22SrTiO3 ceramic by internal clamping

“…This is due to clamping enhanced pyroelectric coefficient, the mechanism of which has been already discussed in detail. [55][56][57] Additionally, room temperature dielectric constant (ε) and loss (tan δ) as a function of frequency have been measured. Figures 6(a) and 6(b), represent dielectric constant (ε) and loss (tan δ) respectively for pure and glass added BNT-BT-ST ceramics.…”

Towards reversible control of domain wall conduction in Pb(Zr0.2Ti0.8)O3 thin films

“…We note that our previous studies on perovskite ferroelectrics 20,21 showed no significant differences in the structural or the functional properties between films grown on the same substrates by the two different methods, making the choice of substrate the defining parameter in our study. We could therefore compare domain wall transport in samples with very different oxygen vacancy densities and substrate chemical properties 22 but similar high crystalline 23,24 and surface quality.…”

Effect of domain walls on the electrocaloric properties of Pb(Zr1−x,Tix)O3 thin films

“…The first term represents the intrinsic electrocaloric response due to a temperature dependent change in the magnitude of the polarization within the domains. Since the equilibrium c domain population / 0 depends on temperature, we also have an extrinsic contribution 19 to the primary electrocaloric coefficient as shown in the second term. The polydomain thermodynamic theory enables us to calculate the intrinsic and extrinsic contributions as a function of the applied electric field.…”