04/16 (목) 전문가초청특강은 숭실대학교 박세영 교수님을 모시고 진행합니다.

관심있는 분들의 많은 참석 부탁드립니다.

ㅁ주제: Designing materials with switchable polarization by artificial structuring

ㅁ일시: 04/16 (목) 16:00

ㅁ장소: 제2종합연구동 83188호

ㅁ약력: 

ㅁ초록:

In this talk, I first introduce the notion of emergent symmetry breaking in condensed matter systems in which the symmetry of the ground-state wavefunction is spontaneously broken, with examples exhibiting such symmetry breakings. Then, a case regarding the broken inversion symmetry is discussed with a new design principle to fabricate an artificial polar material by combining charge-ordering and superlattice layering. As the demonstration of the proposed design principle, I discuss the artificial structuring of the experimentally reported mixed-valence solid-solution La_1/3Sr_2/3FeO₃ (LSFO). Our density functional theory calculations show that A-site (111)-layered LSFO exhibits a ferroelectric charge-ordered phase in which the inversion symmetry breaking is induced by changing the registry of the charge order with respect to the superlattice layering. Our calculations reveal that the artificial structuring of LSFO and other mixed-valence oxides with robust charge ordering in the solid solution phase can lead to charge-order-induced ferroelectricity.