We present calculations of the charge density profile, subband occupancy and ellipsometry spectra of the electron gas at the LaAlO3/SrTiO3 interface. The calculations employ self-consistent Hartree and random phase approximations, a tight binding parametrization of the band structure and a model for the optical phonon of SrTiO3. The dependence of the spatial structure and occupancy of subbands on the magnitude of the polarization charge at the interface and the dielectric function is determined. The interface-confined subbands may be labelled by the symmetry (xy, xz, or yz) of the Ti d-orbitals from which they mainly derive. The xy-derived band nearest the interface contains the major proportion of the electronic charge, but a large number of more distant, slightly occupied xy-derived bands are also found. Depending on the magnitude of the polarization charge, zero, one, or two xz/yz derived subbands are found. When present, these xz/yz bands give the dominant contribution to the long-distance tail of the interface charge. The response to applied ac electric fields polarized parallel and perpendicular to the interface is calculated and the results are presented in terms of ellipsometry angles. Two features are found: a dip in the spectrum near the LO feature of the STO phonon and a peak at the higher energy. We show that the form and magnitude of the dip is related to the Drude response of carriers moving in the plane of the interface while the peak arises from the plasmon excitation of the xz and yz electrons. The relation of the features of the subband occupancies and the in-plane conductivities is given.
Size dependent electric voltage-controlled magnetic anisotropy in multiferroic heterostructures: Interface-charge and strain co-mediated magnetoelectric coupling
Competition between covalent bonding and charge transfer at complex-oxide interfaces
在这里，我们研究了铜酸盐/锰氧化物界面的电子性质。利用原子分辨电子显微镜和能谱技术，我们制作了一幅亚纳米尺度的过渡金属氧化态分布图，它位于高$T_c$超导体YBa $_2$ Cu $_3$ O $_{7-δ}$和巨磁电阻化合物（La，Ca）MnO $_3$之间的界面上.电子从锰氧化物到铜氧化物的净转移具有特殊的非单调电荷分布。模型计算合理化的配置文件之间的竞争标准的电荷转移趋势（由于带失配），强化学键合效应的界面，和Cu取代到Mn晶格，具有不同的特征长度尺度。
