Cao Shi, Paudel Tula R, Sinha Kishan, Jiang Xuanyuan, Wang Wenbin, Tsymbal Evgeny Y, Xu Xiaoshan, Dowben Peter A
Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588, USA.
J Phys Condens Matter. 2015 May 8;27(17):175004. doi: 10.1088/0953-8984/27/17/175004. Epub 2015 Mar 20.
The surface termination and the nominal valence states for hexagonal LuFeO3 thin films grown on Al2O3(0 0 0 1) substrates were characterized by angle resolved x-ray photoemission spectroscopy. The Lu 4f, Fe 2p and O 1s core level spectra indicate that both the surface termination and the nominal valence depend on surface preparation, but the stable surface terminates in a Fe-O layer. This is consistent with the results of density functional calculations which predict that the Fe-O termination of LuFeO3(0 0 0 1) surface is energetically favorable and stable over a broad range of temperatures and oxygen partial pressures when it is reconstructed to eliminate surface polarity.
采用角分辨X射线光电子能谱对生长在Al2O3(0 0 0 1)衬底上的六角形LuFeO3薄膜的表面终止和名义价态进行了表征。Lu 4f、Fe 2p和O 1s芯能级谱表明，表面终止和名义价态均取决于表面制备，但稳定的表面终止于Fe-O层。这与密度泛函计算结果一致，该计算预测，当LuFeO3(0 0 0 1)表面的Fe-O终止被重构以消除表面极性时，在很宽的温度和氧分压范围内，其在能量上是有利的且稳定的。
