[9a-P02-1~24] 6.3 Oxide electronics

[9a-P02-3] Single Crystalline Growth of LuFe₂O₄ Thin Films via Surface Structure Control of Substrates towards Electrical Manipulation of the Charge Ordering

〇Atsushi Fukuchi¹, Hiroyuki Kobayashi², Hiroki Arisawa^1,3,4, Eiji Saitoh^1,3,4,5,6, Satoshi Okamoto^1,2 (1.UT-Sumitomo Chemical Cooperation Program, 2.Sumitomo Chemical Collaborative Research Cluster, 3.Dept. Appl. Phys, Univ. Tokyo, 4.RIKEN CEMS, 5.BAI Univ. Tokyo, 6.AIMR Tohoku Univ.)

Keywords:

charge ordering,electronic ferroelectric,novel memory technology

Mixed valence materials after the charge ordering intrinsically have a finite polarization in the structures because of spatial imbalance of the ordered charges. Although control of such polarization by electrical stimuli has rarely been demonstrated in the systems, the control is believed to have a great potential in application fields because the polarization changes are purely electronic and do not accompany ion displacement in structures. In this study, we grew epitaxial thin films of charge-ordering oxide LuFe₂O₄ on YSZ (111) substrates and investigated the crystallographic and charge-ordering structures in detail to obtain clues for the device applications. We observed that single crystalline epitaxial growth of LuFe₂O₄ is significantly facilitated by forming periodic step-and-terrace structures on the YSZ (111) surfaces, and a signature of charge ordering was successfully observed above room temperature in the LuFe₂O₄ thin films after the surface treatments for YSZ.