arXiv 0810.52312008-10-29cond-mat.mtrl-scicond-mat.str-el

Tetragonal CuO: A new end member of the 3d transition metal monoxides

Wolter Siemons, Gertjan Koster, Dave H. A. Blank, Robert H. Hammond, Theodore H. Geballe, Malcolm R. Beasley

DOI：: 10.1103/PhysRevB.79.195122

英文摘要：

Monoclinic CuO is anomalous both structurally as well as electronically in the 3$d$ transition metal oxide series. All the others have the cubic rock salt structure. Here we report the synthesis and electronic property determination of a tetragonal (elongated rock salt) form of CuO created using an epitaxial thin film deposition approach. In situ photoelectron spectroscopy suggests an enhanced charge transfer gap $Δ$ with the overall bonding more ionic. As an end member of the 3d transition monoxides, its magnetic properties should be that of a high $T_N$ antiferromagnet.

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