Perovskite oxides: new functions by epitaxial design. Pulsed laser deposition.

Seminārs attālināti un angļu valodā

Par semināru:

Metal oxides, which possess generic formula ABO3 (A, B - metals) and adopt perovskite-type crystal structure, represent a broad class of multifunctional materials. Numerous perovskite oxides have been synthesized in the form of bulk ceramics or crystals. These oxides demonstrate electronic states varying from perfect insulator to superconductor and exhibit remarkable effects and strong response function to electric, magnetic, or stress fields, light, and temperature. Many of perovskite functional properties enable commercialized applications in diverse fields of electronics, photonics, and catalysis. New perovskites are continuously being prepared by varying combinations of metal constituents. However, global environmental issues and modern device-specific issues, as well as fundamental scientific interest stimulate research of single-crystal thin films, or epitaxial films of perovskite oxides. Notably, epitaxy allows for achieving unprecedented crystal phases and functional responses, not available in bulk materials.

In this lecture, basics of perovskite oxides and main functional classes of these materials, as well as principle notations of epitaxial films will be briefly introduced. Modern approaches to epitaxial control of properties of perovskite oxides will be presented.

Pulsed laser deposition (PLD) is a deposition technique, which allows for rather high oxygen pressure during thin-film growth. Therefore, it is best-suited for deposition of oxides, including perovskite oxides. The technique is flexible with respect to the film material, that enables in situ growth of not only diverse films, but also complex multilayers of different materials. Being excellent as a research technique, PLD is also entering industrial technological lines.

In this lecture, basic idea and setup for PLD will be introduced. The key physical processes, which are involved in PLD, will be briefly described. Correlations between PLD parameters and film growth will be discussed.