摘要
The magnetism,the magnetocrystalline anisotropy and the optical properties of the monolayer and atomic chain of 4d transition-metal Ru are investigated by using the full-potential linearized-augmented-plane-wave method in a generalized gradient approximation.The magnetic moments are 1.039 μВ/atom and 1.130 μВ/atom for the monolayer and atomic chain,respectively. Both systems have large magnetocrystalline anisotropy energy （MAE）.The magaetic easy axis is normal to the monolayer and perpendicular to the chain axis in the atomic chain.The optical properties of the two low-dimensional Ru systems are investigated by calculating the complex optical conductivity tensor.Both systems exhibit anisotropy in photoconductivity,especially for the atomic chain.The physical origins of MAE and photoconductivity are studied based on electronic structures.It is found that the changes in crystal field caused by different symmetry-breaking mechanisms in the two low-dimensional Ru systems result in MAE through spin-orbit coupling,while the anisotropy in photoconductivity mainly comes from the crystallographic anisotropy.
The magnetism,the magnetocrystalline anisotropy and the optical properties of the monolayer and atomic chain of 4d transition-metal Ru are investigated by using the full-potential linearized-augmented-plane-wave method in a generalized gradient approximation.The magnetic moments are 1.039 μВ/atom and 1.130 μВ/atom for the monolayer and atomic chain,respectively. Both systems have large magnetocrystalline anisotropy energy （MAE）.The magaetic easy axis is normal to the monolayer and perpendicular to the chain axis in the atomic chain.The optical properties of the two low-dimensional Ru systems are investigated by calculating the complex optical conductivity tensor.Both systems exhibit anisotropy in photoconductivity,especially for the atomic chain.The physical origins of MAE and photoconductivity are studied based on electronic structures.It is found that the changes in crystal field caused by different symmetry-breaking mechanisms in the two low-dimensional Ru systems result in MAE through spin-orbit coupling,while the anisotropy in photoconductivity mainly comes from the crystallographic anisotropy.
基金
Project supported by the National Natural Science Foundation of China (Grant Nos 90505007 and 10774061)
