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arXiv · 2402.18763

Discovery of magnetic phase transitions in heavy-fermion superconductor CeRh$_2$As$_2$

Grzegorz Chajewski·Dariusz Kaczorowski
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Abstract

We report on the specific heat studies performed on a new generation of CeRh$_2$As$_2$ single crystals. Superior quality of the samples and dedicated experimental protocol allowed us to observe an antiferromagnetic-like behavior in the normal state and to detect the first-order phase transition of magnetic origin within the superconducting state of the compound. Although in the available literature the physical behavior of CeRh$_2$As$_2$ is most often described with the use of quadrupole density wave scenario, we propose an alternative explanation using analogies to antiferromagnetic heavy-fermion superconductors CeRhIn$_5$ and Ce$_2$RhIn$_8$.

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Grzegorz Chajewski, Dariusz Kaczorowski. 2024-02-29. Discovery of magnetic phase transitions in heavy-fermion superconductor CeRh$_2$As$_2$. https://doi.org/10.1103/physrevlett.132.076504

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