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Self-consistent spin fluctuation spectrum and correlated electronic structure of actinides

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Abstract

We present an overview of various theoretical methods with detailed emphasis on an intermediate Coulomb-U coupling model. This model is based on material-specific ab initio band structure from which correlation effects are computed via self-consistent GW-based self-energy corrections arising from spin fluctuations. We apply this approach to four isostructural intermetallic actinides PuCoIn5, PuCoGa5, PuRhGa5 belonging to the Pu-115 family, and UCoGa5 a member of the U-115 family. The 115 families share the property of spin–orbit split density of states enabling substantial spin fluctuations around 0.5 eV, whose feedback effect on the electronic structure creates mass renormalization and electronic “hot spots,” i.e., regions of large spectral weight. A detailed comparison is provided for the angle-resolved and angle-integrated photoemission spectra and de Haas–van Alphen experimental data as available. The results suggest that this class of actinides is adequately described by the intermediate Coulomb interaction regime, where both itinerant and incoherent features coexist in the electronic structure.

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ACKNOWLEDGMENTS

We thank T. Durakiewicz, J.J. Joyce, A.V. Balatsky, R.S. Markiewicz, A. Bansil, P. Werner, P. Oppeneer, F. Ronning, and E.D. Bauer for discussions. Work at the Los Alamos National Laboratory was supported by the U.S. DOE under Contract No. DE-AC52-06NA25396 through the LDRD Program and BES (T.D.), Division of Materials Sciences and Engineering. We acknowledge computing allocations by NERSC through the Office of Science (BES) under Contract No. DE-AC02-05CH11231.

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Das, T., Zhu, JX. & Graf, M.J. Self-consistent spin fluctuation spectrum and correlated electronic structure of actinides. Journal of Materials Research 28, 659–672 (2013). https://doi.org/10.1557/jmr.2012.423

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