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arXiv · 0906.3078

4f-derived Fermi Surfaces of CeRu2(Si[1-x]Ge[x])2 near the Quantum Critical Point: Resonant Soft X-ray ARPES Study

T. Okane·T. Ohkochi·Y. Takeda·S. -i. Fujimori·A. Yasui·Y. Saitoh·H. Yamagami·A. Fujimori·Y. Matsumoto·M. Sugi·N. Kimura·T. Komatsubara·H. Aoki
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Abstract

Angle-resolved photoelectron spectroscopy in the Ce 3d-4f excitation region was measured for the paramagnetic state of CeRu2Si2, CeRu2(Si0.82Ge0.18)2, and LaRu2Si2 to investigate the changes of the 4$f$ electron Fermi surfaces around the quantum critical point. While the difference of the Fermi surfaces between CeRu2Si2 and LaRu2Si2 was experimentally confirmed, a strong 4f-electron character was observed in the band structures and the Fermi surfaces of CeRu2Si2 and CeRu2(Si0.82Ge0.18)2, consequently indicating a delocalized nature of the 4$f$ electrons in both compounds. The absence of Fermi surface reconstruction across the critical composition suggests that SDW quantum criticality is more appropriate than local quantum criticality in CeRu2(Si[1-x]Ge[x])2.

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T. Okane, T. Ohkochi, Y. Takeda, S. -i. Fujimori, A. Yasui, Y. Saitoh, H. Yamagami, A. Fujimori, Y. Matsumoto, M. Sugi, N. Kimura, T. Komatsubara, H. Aoki. 2009-06-17. 4f-derived Fermi Surfaces of CeRu2(Si[1-x]Ge[x])2 near the Quantum Critical Point: Resonant Soft X-ray ARPES Study. https://doi.org/10.1103/physrevlett.102.216401

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