论文标题
基于SRTIO3的异质结构中的可调旋转和轨道极化
Tunable spin and orbital polarization in SrTiO3-based heterostructures
论文作者
论文摘要
我们在$ \ mathrm {laalo_3/srtio_3} $（lao/sto）异质结构中制定了Rashba Spin-Orbit耦合（RSOC）的有效哈密顿。我们将属性的分析表达式（例如Rashba参数，有效质量，带边缘能量和轨道占用）作为材料和可调异质结构参数的功能。虽然线性RSOC在$γ$ - 点均具有主导地位，但立方RSOC在更高能量的抗跨区域变得很重要。我们发现线性RSOC源于结构反转不对称（SIA），而Cutic项则由SIA和BOLLK不对称性诱导。此外，SOC强度显示出对可调异质结构参数（例如sto厚度和界面电场）的显着依赖性，该参数归因于老挝/STO界面附近的量子限制效应。线性和立方RSOC的计算值与先前的实验结果一致。
We formulate the effective Hamiltonian of Rashba spin-orbit coupling (RSOC) in $\mathrm{LaAlO_3/SrTiO_3}$ (LAO/STO) heterostructures. We derive analytical expressions of properties, e.g., Rashba parameter, effective mass, band edge energy and orbital occupancy, as functions of material and tunable heterostructure parameters. While linear RSOC is dominant around the $Γ$-point, cubic RSOC becomes significant at the higher-energy anti-crossing region. We find that linear RSOC stems from the structural inversion asymmetry (SIA), while the cubic term is induced by both SIA and bulk asymmetry. Furthermore, the SOC strength shows a striking dependence on the tunable heterostructure parameters such as STO thickness and the interfacial electric field which is ascribed to the quantum confinement effect near the LAO/STO interface. The calculated values of the linear and cubic RSOC are in agreement with previous experimental results.
