title: Orbital orderings and optical conductivity of SrRuO(3) and CaRuO(3): first-principles studies.
abstract: The Jahn-Teller (JT) distortion induced orbital order and optical conductivity in SrRuO(3) and CaRuO(3) are investigated by first-principles calculations. The total energy and optical conductivity of all the spin ordering states of SrRuO(3) and CaRuO(3) are calculated in the LDA+U scheme with U(eff) = 2.5 eV. The down-spin t(2g) of Ru show antiferromagnetic-like orbital order in the a-b plane. We observe a d-d transition peak at an energy of about 1.0 eV in the calculated optical conductivity and analyze the reason for it not being observed in previous experiments.
authors.affiliation: Department of Physics, Henan Normal University, Xinxiang, Henan 453007, People's Republic of China. Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: Guang-Tao
authors.initials: GT
authors.lastname: Wang
authors.forename: Min-Ping
authors.initials: MP
authors.lastname: Zhang
authors.forename: Zong-Xian
authors.initials: ZX
authors.lastname: Yang
authors.forename: Zhong
authors.initials: Z
authors.lastname: Fang