[15p-WL2_101-1~13] 6.3 Oxide electronics

2:00 PM - 2:15 PM JST(5:00 AM - 5:15 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[15p-WL2_101-3] Structual properties of Ti₂O₃ films grown on van der Waals hBN multilayers

〇Keitaro Kanno¹, Takuto Soma¹, Satoru Fukamachi², Hiroki Ago², Hironori Nakao³, Akira Ohtomo¹, Kohei Yoshimatsu¹ (1.Science Tokyo, 2.Kyushu Univ., 3.KEK-IMSS)

Keywords:

transition metal oxide,metal-insulator transition,hBN

Ti₂O₃ exhibits a metal-insulator transition (MIT) governed by the crystallographic c/a ratio. However, films grown on α-Al₂O₃ suffer from compressive strain, suppressing the MIT. We previously reported that Ti₂O₃ films grown on van der Waals (vdW) hBN multilayers recover bulk-like MIT characteristics. In this study, we investigated the structural properties of Ti₂O₃/hBN films using synchrotron X-ray diffraction. A φ-scan of the 11-26 reflection revealed a 30° periodicity, corresponding to the rotational alignment of the underlying hBN grains, indicating local epitaxial growth. Reciprocal space mapping yielded lattice constants of a = 5.13 Å and c = 13.71 Å (c/a = 2.67). This reduced c/a ratio suggests that the vdW interface significantly relaxes in-plane compressive stress, enabling the recovery of bulk-like MIT.