Puggioni Danilo, Rondinelli James M
Department of Materials Science & Engineering, Drexel University, Philadelphia, PA, 19104, USA.
J Phys Condens Matter. 2014 Jul 2;26(26):265501. doi: 10.1088/0953-8984/26/26/265501. Epub 2014 Jun 9.
Using first-principles calculations, we compute the linear optical properties for cation ordered (Sr,Ca)Ru2O6. Our calculations show that this polar ferromagnetic metallic oxide exhibits optical anisotropy along the principal directions of the optical indicatrix owing to the absence of inversion symmetry in the crystal structure. The calculated reflectivity is used to locate the onset of the inter-band transitions at an energy of 1.3 eV. Comparing the optical conductivity with the electronic band structure, we identify the possible optical transitions. Finally, we apply the generalized Drude model to deduce an enhancement of the effective mass, m() ∼ 4.9m(e), in ordered (Sr,Ca)Ru2O6. Moreover, we show that removal of the polar distortions decrease the effective mass to m() ∼ 4.4m(e), suggesting that control over the amplitude of the polar displacements could be used to tune the degree of electronic correlation in oxide conductors without inversion symmetry.
通过第一性原理计算，我们计算了阳离子有序的(Sr,Ca)Ru2O6的线性光学性质。我们的计算表明，由于晶体结构中不存在反演对称性，这种极性铁磁金属氧化物在光学指示体的主方向上表现出光学各向异性。计算得到的反射率用于确定带间跃迁在1.3 eV能量处的起始点。将光导率与电子能带结构进行比较，我们确定了可能的光学跃迁。最后，我们应用广义德鲁德模型推导出有序(Sr,Ca)Ru2O6中有效质量m() ∼ 4.9m(e)的增强。此外，我们表明消除极性畸变会使有效质量降至m() ∼ 4.4m(e)，这表明控制极性位移的幅度可用于调节无反演对称性的氧化物导体中的电子关联程度。
