TY  - THES
AB  - It is known that the dynamics of ferroelectric materials can be seen over a range of macroscopic, microscopic, and mesoscopic length scales. Thus, the response time of ferroelectrics due to an external perturbation will change on each specific length scale. In particular, the atomic dynamics occurs much faster compared to the response of the macroscopic lattice, whereas time scales of mesoscopic dynamics are a mixture ranging from the nano- to the milli-second regime. Developing an experimental method that covers multiple time scales allows for selective identification of the specific changes on each time scale and their influence on the ferroelectrics. If an experimental approach can be developed with multiple time resolutions, the response of the ferroelectrics can be selectively identified the dominant time and length scales under an external perturbation. Stroboscopic time-resolved X-ray diffraction is a very powerful tool to probe dynamical changes in ferroelectrics. Using a multi-channel analyzer data-acquisition system with nanosecond time resolution opens the possibility of observing the dynamics of ferroelectrics on multiple length scales. This state-of-the-art method allows for a better understanding of the dynamic processes in ferroelectrics and provides new insights for the design of advanced (e.g. smart and environmentally friendly) functional materials. 
The development of the new data-acquisition systems and their applications in stroboscopic time-resolved X-ray diffraction are described in Chapter 4. Chapter 5 studies the relationship between the piezoelectricity and the polarization rotation of Na0.5Bi0.5TiO3 (NBT) single crystal under an alternating electric field using synchrotron-based time-resolved high-resolution reciprocal space mapping. Chapter 6 investigates the origin of the enhanced piezoelectric activity in uniaxial Sr0.5Ba0.5Nb2O6 (SBN50) ferroelectrics. Chapter 7 discusses the mechanism of the electric field-induced polarization reversal and strain in perovskite-based 0.94BaTiO3-0.06BiZn0.5Ti0.5O3 (BT-BZT) ferroelectric ceramics under an alternating electric field using stroboscopic time-resolved high-energy X-ray powder diffraction.
AU  - Choe, Hyeokmin
DA  - 2018
KW  - Röntgenbeugung / Zeitauflösung
KW  - Ferroelectrics
KW  - Time-resolved X-ray diffraction
LA  - eng
PY  - 2018
TI  - Dynamics of strain and domains in single crystal and ceramic ferroelectrics under an alternating electric field using stroboscopic time-resolved X-ray diffraction
UR  - https://nbn-resolving.org/urn:nbn:de:hbz:467-13205
Y2  - 2024-11-22T01:21:46
ER  -