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Band structure of LaB6 by an algorithm for filtering reconstructed electron-positron momentum densities

G. Kontrym-Sznajd·M. Samsel-Czekala·M. Biasini·Y. Kubo
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Abstract

A new method (NM) for filtering three-dimensional reconstructed densities is proposed. The algorithm is tested with simulated spectra and employed to study the electronic structure of the rare-earth compound LaB6. For this system, momentum densities are reconstructed from theoretical and experimental two-dimensional angular correlation of electron-positron annihilation radiation (2D ACAR) spectra. The experimental results are in good agreement with the band structure calculated with the full-potential linearized augmented-plane-wave (FLAPW) method within the local-density approximation (LDA), apart from the detection of small electron pockets in the 15th band. It is also shown that, unlike the electron-positron enhancement, the electron-electron correlations affect noticeably the momentum density.

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G. Kontrym-Sznajd, M. Samsel-Czekala, M. Biasini, Y. Kubo. 2004-09-17. Band structure of LaB6 by an algorithm for filtering reconstructed electron-positron momentum densities. https://doi.org/10.1103/physrevb.70.125103

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