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arXiv · 1704.02139

Drastic change of the Fermi surface across the metamagnetic transition in CeRh$_2$Si$_2$

K. Götze·D. Aoki·F. Lévy-Bertrand·H. Harima·I. Sheikin
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Abstract

We report high field de Haas-van Alphen (dHvA) effect measurements in CeRh$_2$Si$_2$ both below and above the first-order 26 T metamagnetic transition from an antiferromagnetic to a polarized paramagnetic state. The dHvA frequencies observed above the transition are much higher than those observed below, implying a drastic change of the Fermi-surface size. The dHvA frequencies above the transition and their angular dependence are in good agreement with band-structure calculations for LaRh$_2$Si$_2$, which correspond to CeRh$_2$Si$_2$ with localized $f$ electrons. Given that the $f$ electrons are also localized at low fields in CeRh$_2$Si$_2$, the Fermi-surface reconstruction is due to the suppression of antiferromagnetism and the restoration of the crystallographic Brillouin zone rather than the delocalization of the $f$ electrons. This example suggests that the intuitive notation of "small" and "large" Fermi surfaces commonly used for localized and itinerant $f$ electrons, respectively, requires careful consideration, taking into account the modification of the Brillouin zone in the antiferromagnetic state, when interpreting experimental results.

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K. Götze, D. Aoki, F. Lévy-Bertrand, H. Harima, I. Sheikin. 2017-04-07. Drastic change of the Fermi surface across the metamagnetic transition in CeRh$_2$Si$_2$. https://doi.org/10.1103/physrevb.95.161107

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