Department of Physics, Indian Institute of Technology, Kanpur, India.
J Phys Condens Matter. 2012 Feb 29;24(8):086003. doi: 10.1088/0953-8984/24/8/086003. Epub 2012 Jan 26.
The onset and melting of locally staggered charge/orbital correlations is investigated within a two-orbital correlated electron model with inter-orbital and inter-site Coulomb interactions. The CE-type orbital correlation exhibits a sharp onset close to the Curie temperature and rapid thermal melting thereafter, which provides quantitative understanding of the (π/2,π/2,0) feature observed in neutron scattering experiments on La(0.7)(Ca(y)Sr(1-y))(0.3)MnO(3) single crystals. In the zig-zag AF state, the CE-type orbital correlations are found to be even more readily stabilized, but only within a narrow doping regime around x = 0.5.
本文在包含轨道间和晶间库仑相互作用的双轨道关联电子模型中，研究了局域交错电荷/轨道关联的起始和融化过程。CE 型轨道关联在接近居里温度时出现急剧的起始，并随后迅速热融化，这为在 La(0.7)(Ca(y)Sr(1-y))(0.3)MnO(3)单晶的中子散射实验中观察到的(π/2,π/2,0)特征提供了定量理解。在锯齿型反铁磁态中，CE 型轨道关联被发现更容易稳定，但仅在 x = 0.5 左右的狭窄掺杂范围内。
