Terahertz response of SrTiO.sub.3./sub. based heterostructures: Influence of strain temperature and electric field

0486580 - FZÚ 2018 RIV US eng C - Konferenční příspěvek (zahraniční konf.)
Skoromets, Volodymyr - Kadlec, Christelle - Drahokoupil, Jan - Schubert, J. - Kužel, Petr
Terahertz response of SrTiO₃ based heterostructures: Influence of strain temperature and electric field.
Proceedings of the 39th International Conference on Infrared Millimeter and Terahertz Waves. New York: IEEE, 2014, s. 1-2, č. článku 6956088. ISBN 978-147993877-3. ISSN 2162-2027.
[39th International Conference on Infrared Millimeter and Terahertz Waves. Tucson (US), 14.09.2014-19.09.2014]
Institucionální podpora: RVO:68378271
Klíčová slova: SrTiO₃ * terahertz * strained multilayers * tuneability * ferroelectric
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)

A systematic study of strained SrTiO3/DyScO3 heterostructures was performed using time-domain terahertz spectroscopy in the temperature range from 20 to 294 K. Interdigitated electrodes deposited on top of the structures allowed probing of the terahertz response upon an applied electric field. All studied structures underwent the phase transition close to room temperature. Evolution of the complex dielectric spectra with temperature and electric bias was described by a general model involving a harmonic oscillator (soft mode) coupled to a Debye relaxation (central mode). At high temperatures, the soft mode is responsible for nearly all the changes observed in the spectra with temperature and applied electric field. At low temperatures, deep in the ferroelectric phase, the soft mode significantly hardens and loses its importance for the terahertz dynamics, the central mode becomes stronger and it almost completely determines the shape of the measured spectra.

Trvalý link: http://hdl.handle.net/11104/0281338