Fermi surface changes due to localized-delocalized f-state transitions in Ce-115 and Pu-115 compounds
2007 (English)In: Journal of Magnetism and Magnetic Materials, ISSN 0304-8853, Vol. 310, no 2, 1684-1690 p.Article in journal (Refereed) Published
The current theoretical understanding of the electronic structures of the CeMIn5 compounds (with M = Co, Rh, and Ir) and PuCoGa5 and PuRhGa5 is reviewed. Both the Ce-115 and Pu-115 compounds have in common that their f-electrons appear to be poised on the edge of a localization-delocalization boundary. We consider here the implications of this characteristic on the emergent electronic structure, addressing, in particular, the computed Fermi surfaces. In order to capture the electronic structures to the best as possible, we employ three different density-functional theory based computational approaches, viz. the local-spin density approximation (LSDA) for delocalized f-states, the open-core approach for localized f's, and the LSDA + U approach for moderately localized f's. The Fermi surfaces of CeCoIn5 and CeIrIn5 are rather well described assuming delocalized 4f electrons. Conversely, the better description is obtained for CeRhIn5 assuming a localized 4f state. For the Pu-115 compounds, LSDA calculations predict a rather two-dimensional Fermi surface. However, the Fermi surface of PuCoGa5 computed with the around-mean field LSDA + U scheme is also quite two-dimensional and, moreover, similar to the LSDA Fermi surface. Taking other available experimental data on PuCoGa5 into account, it appears that the electronic structure of PuCoGa5 is best described by the AMF-LSDA + U approach with a Coulomb U of about 3 eV.
Place, publisher, year, edition, pages
2007. Vol. 310, no 2, 1684-1690 p.
Ce-115 compounds, PuCoGa5, Fermi surface, LSDA plus U calculations, unconventional superconductivity
IdentifiersURN: urn:nbn:se:uu:diva-151495DOI: 10.1016/j.jmmm.2006.10.763ISI: 000247618700379OAI: oai:DiVA.org:uu-151495DiVA: diva2:410228