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arXiv · 2503.09524

Pressure-induced strange metal phase in a metallic kagome ferromagnet

Bin Shen·Feng Du·Franziska Breitner·Victoria A. Ginga·Ece Uykur·Alexander A. Tsirlin·Philipp Gegenwart
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Abstract

Strange metallicity with $T$-linear electrical resistance preceding high-$T_c$ superconductivity remains an enigmatic, yet crucial, signature of correlation physics. Using electrical transport and magnetization measurements up to 50 GPa, we show that such a strange-metal phase is formed in pressurized kagome ferromagnet CrNiAs. In contrast to other kagome materials, a linear suppression of the Curie temperature is found, with the ferromagnetic quantum critical point at $p_{\rm{c}} \approx 12.5$ GPa. Remarkably, from $p_{\rm{c}}$ up to the highest measured pressure, characteristic strange-metal behavior is observed, whereas magnetic field reinstates the Fermi liquid. Electronic structure calculations reveal robust weakly dispersive bands persisting unchanged beyond $p_{\rm{c}}$, possibly at the origin of the $T$-linear electrical resistance. This establishes pressurized kagome ferromagnets as an intriguing platform for strange-metal behavior.

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Bin Shen, Feng Du, Franziska Breitner, Victoria A. Ginga, Ece Uykur, Alexander A. Tsirlin, Philipp Gegenwart. 2025-03-12. Pressure-induced strange metal phase in a metallic kagome ferromagnet. https://arxiv.org/abs/2503.09524

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