[18p-E311-1~18] 6.3 酸化物エレクトロニクス

▼ [18p-E311-4] Electrical Transport and Magnetic Properties of LuFe₂O₄ Epitaxial Thin Films

〇(D)YouJin Kim¹、Shinya Konishi¹、Yuichiro Hayasaka²、Itsuhiro Kakeya³、Katsuhisa Tanaka¹ (1.Department of Material Chemistry, Graduate School of Engineering, Kyoto Univ.、2.The Electronic Microscopy Center, Tohoku Univ.、3.Departement of Electronic Science and Engineering, Graduate School of Engineering ,Kyoto Univ.)

キーワード：hexagonal ferrite, exchange bias effect, Mott-VRH

Among the RFe₂O₄ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404606859699177400">compounds</gwmw>, structure and properties of LuFe₂O₄ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404733363500944780">have</gwmw> been <gwmw class="ginger-module-highlighter-mistake-type-3" id="gwmw-15613404733368246098750">most extensively</gwmw> explored, but most of the studies have been performed for bulk materials. In contrast, there are not so many reports on thin film forms of <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404760658434108030">LuFe</gwmw>₂O₄, although the thin films are important, especially from a point of view of device applications. In the present study, we report on magnetic and electrical properties of <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404905065512319697">LuFe</gwmw>₂O₄ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404935479536487846">thin</gwmw> films prepared by a pulsed laser deposition method. We found that hexagonal LuFeO₃ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613404998931205179696">and</gwmw> Lu₂Fe₃O₇ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613405106819767788306">phases</gwmw> of very thin layers were formed at the interface between the LuFe₂O₄ <gwmw class="ginger-module-highlighter-mistake-type-1" id="gwmw-15613405131522510063030">thin</gwmw> films and the substrate, and such a structure led to large exchange bias effect. In addition, we measured the temperature dependence of electrical resistivity and observed a change in electronic transport behavior from thermal activation scheme to 3D Mott-variable range hopping at the charge ordering temperature.