Progress in the theoretical description of a strongly frustrated edge-shared model chain cuprate: Li2CuO2
Year: 2010
Type: conference-paper
Abstract: We report an essentially improved microscopic understanding of the leading in-chain NN and NNN exchange integrals J 1 and J 2 for the prototype title compound. It is based on a novel analysis of the optical conductivity σ( ω , T ) within a five-band extended Hubbard model the O 1 s x-ray absorption and other spectroscopic data using exact diagonalizations, the DMRG technique, and L(S)DA+ U calculations, as well as a spin-wave fit of new inelastic neutron data for Li 2 CuO 2 . Here a highly dispersive magnetic excitation has been detected for the first time. It gives rise to a more than twice as large ferromagnetic J 1 ~ −230 K and to a smaller in-chain frustration ratio − J 2 / J 1 = 0.33 ± 0.01 as compared with the results based on a different microscopic parameter set proposed by Mizuno et al. 1998 Phys. Rev. B 57 5326. The frustrated inter-chain interaction is found to be responsible for the FM ordering.
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W1968662428