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Ferroelectric materials have the ability to convert electrical energy into mechanical energy and vice versa, which makes them widely used as sensors, actuators, and ultrasonic transducers. While their electrical and electromechanical properties are well studied, mechanical properties like Young’s modulus (E) and hardness (H) remain known to a lesser extent. …

Fabrication of electroceramics usually requires high sintering temperatures of 800 to 1400 °C, which can unintentionally lead to problems such as volatilization of species, formation of secondary phases and excessive grain growth. These problems can cause inhomogeneous microstructures, non-stoichiometric chemical compositions and limited material functionality. Therefore, there is a need …

The first part of the thesis deals with the impact of surface-functionalized nanoparticles (NP) can have on the stability of liquid crystal (LC) phases. Experimental data of NP concentration-driven phase transition between the isotropic and nematic phase in 5OO8 LCs were used to create a minimal mathematical model that would …

Ferroelectric domain walls (DWs) are nano-to-atomic-scale interfaces that separate domains of different polar order. What makes DWs so interesting is their dynamic nature in an electric field, which offers an exciting potential for nanoscale and atomic-scale applications, but, also, more generally, the dynamics of DWs is linked to a fundamental …

This work presents experimental studies of ordering phenomena, electromechanical and electrocaloric properties in single crystal, ceramic and solid solution relaxor ferroelectrics and single crystal ferroelectric materials. The main aim of investigations is to prove the existence of a liquid-vapor critical point in these systems and to verify its impact on …

KTaO3 belongs to the group of incipient ferroelectrics, which are materials important from the fundamental, as well as from the applications, point of view. It is well known in its single-crystal form; however, the processing of technologically interesting ceramics and thin films is a challenging task and knowledge of their …

In this thesis we demonstrate a new, simple, and ecient method for the solid-state synthesis of oxides with a complex chemical composition. We modify the traditional solidstate synthesis method, which is used in the majority of ceramics laboratories around the world, in order to prepare multi-metallic oxide powders from classic …

The stress dependence of the electrical permittivity offers a convenient way of measuring pressure. This effect is suitable for static and quasi-static stress applications, where the conventional method based on the piezoelectric effect becomes inadequate. Although the principle of applying this effect for pressure sensing has been known for almost …