일시: 2012년 11월 21(수) 오후4:30

장소: 제1과학관 31214  e+첨단강의실

초록: Complex transition metal oxides have attracted a lot of attention because of versatile phenomena and rich physics due to a competition between strongly correlated states with different spin, orbital, and charge. Since the discovery of high T­_c superconductivity, many efforts to synthesize complex oxide compounds in epitaxial film form have been made. We now know basic rules about experimental techniques and materials design. In the talk, I will introduce laser molecular beam epitaxy (L-MBE) technique for growing oxide thin layers with atomic precision and discuss why such epitaxial growths would bring interesting physics. As an example, I will focus on a highly-elongated bismuth ferrite with a high tetragonal factor (c/a ~ 1.26) which is a meta-stable phase competing with the multiferroic bismuth ferrite phase. It is never made in bulk form, but it can be stabilized by hetero-epitaxial growth on special substrates owing to misfit strain. Stabilization of such a meta-stable state gives us another chance to search for new materials. The delicate nature of phase competition and the physical properties of the new meta-stable phase will be presented.