TY - JOUR
T1 - Spatial coherence of the insulating phase in quasi-two-dimensional LaNiO3 films
AU - Anada, Masato
AU - Kowa, Kazuhiro
AU - Maeda, Hiroki
AU - Sakai, Enju
AU - Kitamura, Miho
AU - Kumigashira, Hiroshi
AU - Sakata, Osami
AU - Nakanishi-Ohno, Yoshinori
AU - Okada, Masato
AU - Kimura, Tsuyoshi
AU - Wakabayashi, Yusuke
N1 - Funding Information:
We thank Prof. Y. Morikawa and Dr. H. D. Nguyen for fruitful discussion. This work was supported by a Grant-in-Aid for Scientific Research [Japan Society for the Promotion of Science (JSPS) KAKENHI, Grants No. JP16H02115 and No. JP26105008] and by Japan Science and Technology Agency (JST), PRESTO (Grant No. JPMJPR1773). The synchrotron radiation experiments at the Photon Factory were performed with the approval of the Photon Factory Program Advisory Committee (Proposals No. 2012G091, No. 2013S2-002, No. 2015S2-005, and No. 2015S2-009). The synchrotron diffraction measurements at SPring-8 were performed at the NIMS Synchrotron X-ray Station under Proposals No. 2012B4901 and No. 2013A4901 as part of the NIMS Nanotechnology Platform (Projects No. A-12-NM-0030 and No. A-13-NM-0002).
Publisher Copyright:
© 2018 American Physical Society.
PY - 2018/7/10
Y1 - 2018/7/10
N2 - The quasi-two-dimensional nature of LaNiO3 (LNO) thin films on SrTiO3(001) (STO) and LaAlO3(001) (LAO) substrates is examined. Although both samples undergo a metal-insulator transition with decreasing thickness, the spatial distributions of the insulating phase within the films differ from each other. The LNO cell volume of the insulating phase in LNO/STO is larger than that of the metallic phase, and the large cells remain at the interface in thick films with metallic conduction, suggesting a high oxygen-vacancy content at the interface. The cell volume of the insulating phase in LNO/LAO is smaller than that of the metallic phase, and the cell volume of the entire film changes coherently. The cell-volume decrease indicates that the bonding changes from bulklike to covalent.
AB - The quasi-two-dimensional nature of LaNiO3 (LNO) thin films on SrTiO3(001) (STO) and LaAlO3(001) (LAO) substrates is examined. Although both samples undergo a metal-insulator transition with decreasing thickness, the spatial distributions of the insulating phase within the films differ from each other. The LNO cell volume of the insulating phase in LNO/STO is larger than that of the metallic phase, and the large cells remain at the interface in thick films with metallic conduction, suggesting a high oxygen-vacancy content at the interface. The cell volume of the insulating phase in LNO/LAO is smaller than that of the metallic phase, and the cell volume of the entire film changes coherently. The cell-volume decrease indicates that the bonding changes from bulklike to covalent.
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U2 - 10.1103/PhysRevB.98.014105
DO - 10.1103/PhysRevB.98.014105
M3 - Article
AN - SCOPUS:85049775171
SN - 2469-9950
VL - 98
JO - Physical Review B
JF - Physical Review B
IS - 1
M1 - 014105
ER -