How chemical pressure affects the fundamental properties of rare-earth pnictides: an ARPES view

M. G. Holder; A. Jesche; P. Lombardo; R. Hayn; D. V. Vyalikh; K. Kummer; S. Danzenbächer; C. Krellner; C. Geibel; E. D. L. Rienks; S. L. Molodtsov; C. Laubschat

doi:10.1103/physrevb.86.020506

arXiv · 1207.6340

How chemical pressure affects the fundamental properties of rare-earth pnictides: an ARPES view

M. G. Holder·A. Jesche·P. Lombardo·R. Hayn·D. V. Vyalikh·K. Kummer·S. Danzenbächer·C. Krellner·C. Geibel·E. D. L. Rienks·S. L. Molodtsov·C. Laubschat

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Abstract

Angle-resolved photoelectron spectroscopy, supplemented by theoretical calculations has been applied to study the electronic structure of heavy-fermion material CeFePO, a homologue to the Fe-based high-temperature superconductors, and CeFeAs_0.7P_0.3O, where the applied chemical pressure results in a ferromagnetic order of the 4f moments. A comparative analysis reveals characteristic differences in the Fe-derived band structure for these materials, implying a rather different hybridization of valence electrons to the localized 4f orbitals. In particular, our results suggest that the ferromagnetism of Ce moments in CeFeAs_0.7P_0.3O is mediated mainly by Fe 3d_xz/yz orbitals, while the Kondo screening in CeFePO is instead due to a strong interaction of Fe 3d_3z^2-r^2 orbitals.

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M. G. Holder, A. Jesche, P. Lombardo, R. Hayn, D. V. Vyalikh, K. Kummer, S. Danzenbächer, C. Krellner, C. Geibel, E. D. L. Rienks, S. L. Molodtsov, C. Laubschat. 2012-07-26. How chemical pressure affects the fundamental properties of rare-earth pnictides: an ARPES view. https://doi.org/10.1103/physrevb.86.020506

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