LaAlO3/SrTiO3 oxide heterostructures studied by resonant inelastic x-ray scattering
LaAlO3/SrTiO3 oxide heterostructures studied by resonant inelastic x-ray scattering
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DOI：
10.1103/physrevb.82.241405
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发表时间：
2010-12
影响因子：
3.7
通讯作者：
G. Berner;S. Glawion;J. Walde;F. Pfaff;H. Hollmark;L. Duda;S. Paetel;C. Richter;J. Mannhart;M. Sing;R. Claessen
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文献类型：
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作者：
G. Berner;S. Glawion;J. Walde;F. Pfaff;H. Hollmark;L. Duda;S. Paetel;C. Richter;J. Mannhart;M. Sing;R. Claessen
本文报道了应用共振非弹性X射线散射研究氧化物异质结构LaAlO/sub 3//SrTiO/sub 3/中单导电界面的性质。从钛3d晶体场激发测量在Ti L/分3/共振，我们不仅得到信息的局部几何形状在界面上，但也能够遵循的演变的片状载流子密度与厚度的LaAlO/分3/覆盖层。这些研究结果证实校准后，以前的硬X射线光电子能谱测量的电荷密度从光谱超过一个来自霍尔效应测量，表明在界面处的巡回/i和/本地化的Ti 3d电子的共存。另一方面，我们观察到的电荷载流子浓度的饱和以上的LaAlO/sub 3/厚度的6个单位电池在~1*10/sup 14/ cm/sup-2/，远低于典型的理想的电子重建值。
We report the application of resonant inelastic X-ray scattering to explore the nature of the single conducting interface in the oxide heterostructure LaAlO/sub 3//SrTiO/sub 3/. From the Ti 3d crystal-field excitations measured at the Ti L/sub 3/ resonance we not only derive information on the local geometry at the interface but are also able to follow the evolution of the sheet carrier density with the thickness of the LaAlO/sub 3/ overlayer. These findings confirm after calibration to previous hard X-ray photoelectron spectroscopy measurements that the charge density from spectroscopy exceeds the one derived from Hall-effect measurements, indicating the coexistence of itinerant /i and/ localized Ti 3d electrons at the interface. On the other hand, we observe a saturation of the charge-carrier concentration above a LaAlO/sub 3/ thickness of 6 unit cells at ~1*10/sup 14/ cm/sup -2/, well below the canonical value for ideal electronic reconstruction.