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Observation of three-dimensional bulk Fermi surfaces for a strongly correlated material by soft x-ray $hν$-dependent (700-860 eV) ARPES

M. Yano·A. Sekiyama·H. Fujiwara·T. Saita·S. Imada·T. Muro·Y. Onuki·S. Suga
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Abstract

Three-dimensional Fermi surfaces at a high temperature have been clarified for a strongly correlated Ce compound, ferromagnet CeRu$_2$Ge$_2$ in the paramagnetic phase, by virtue of a soft x-ray $hν$-dependent (700-860 eV) ARPES. Although the observed Fermi surfaces as well as quasiparticle dispersions are partly explained by a band-structure calculation based on a localized $4f$ model, qualitative discrepancy in experiments, between our APRES in the paramagnetic phase and de Haas-van Alphen measurement in the ferromagnetic phase, is revealed. This suggests a fundamental change in the $4f$ contribution to the Fermi surfaces across the magnetic phase transition widely seen for Ce compounds.

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M. Yano, A. Sekiyama, H. Fujiwara, T. Saita, S. Imada, T. Muro, Y. Onuki, S. Suga. 2006-04-30. Observation of three-dimensional bulk Fermi surfaces for a strongly correlated material by soft x-ray $hν$-dependent (700-860 eV) ARPES. https://arxiv.org/abs/cond-mat/0605021

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