Magnetoelektrická vazba a dynamika fázových přechodů v multiferoikách
| Thesis title in Czech: | Magnetoelektrická vazba a dynamika fázových přechodů v multiferoikách |
|---|---|
| Thesis title in English: | Magnetoelectric coupling and dynamics of phase transitions in multiferroics |
| Key words: | magnetismus|feroelektrika|magnetoelektrická vazba|magnóny|elektromagnóny|fonony|THz a infračervená spektroskopie|pevné látky |
| English key words: | magnetism|ferroelectrics|magnetoelectric coupling|magnons|electromagnons|phonons|THz and infrared spectroscopy|solid state |
| Academic year of topic announcement: | 2025/2026 |
| Thesis type: | dissertation |
| Thesis language: | |
| Department: | Student Affairs Department (32-STUD) |
| Supervisor: | RNDr. Stanislav Kamba, CSc. |
| Author: |
| Guidelines |
| Knowladge of solid state physics and English |
| References |
| Charles Kittel: Introduction in Solid State Physics
A. Cano, D. Meier, M. Trassin: Multiferroics - Fundamentals and Applications, De Gruyter 2021 S. Dong, J.-M. Liu, 'S.-W. Cheong, S. Ren. Mutiferroic materials and magnetoelectric physics: symmetry, entanglement, excitations and topology, Advance in Physics 64, 519-626 (2015) S. Kamba. Soft-mode spectroscopy of ferroelectrics and multiferroics: A review. APL Materials 9, 020704 (2021). |
| Preliminary scope of work in English |
| Magnetoelectric coupling in multiferroics is currently a hot topic in solid state physics, not only due to its rich physics but also because of future potential applications in nonvolatile electronic memories, electric field controlled spin filters, magnetoelectric sensors, and so on.
The goal of this thesis will not only be the study of static magnetoelectric coupling (i.e., change of static magnetization by electric field) in various multiferroics, but also the dynamic magnetoelectric coupling responsible for the activation of magnons in terahertz dielectric spectra. Such magnetoelectric excitations are called electromagnons and can, in general, be activated by different mechanisms other than static magnetoelectric coupling. Electromagnons will be investigated using terahertz, infrared and Raman spectroscopy down to liquid helium temperatures and, in some cases, also under external magnetic and electric fields. Static magnetoelectric coupling will be measured using the PPMS and SQUID instruments in the joint lab of FZU and MFF UK. Various materials in the form of single crystals, ceramics and thin films will be investigated. We will focus mainly on high-temperature multiferroics with hexaferrite crystal structure, but also on modern two-dimensional multiferroics with van der Walls bonds. |