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arXiv · 2510.14774

Quantum oscillations and transport properties of layered single-crystal SrCu$_4$As$_2$

Sudip Malick·Michał J. Winiarski·Joanna Bławat·Hanna Świątek·John Singleton·Tomasz Klimczuk
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Abstract

We report a systematic investigation of the physical properties and Fermi-surface topology of layered single-crystal \ce{SrCu4As2} using electrical transport, magnetotransport, and quantum-oscillation experiments plus band-structure calculations. The temperature-dependent electrical resistivity reveals a hysteretic phase transition at $T_P$ = 59 K, most likely associated with a structural change. Hall resistivity data suggest a marked change in the average hole density resulting from the latter phase transition near $T_P$. A large, linear, and nonsaturating magnetoresistance is observed at low temperatures in \ce{SrCu4As2}, likely attributable to the multipocket Fermi surface. Quantum-oscillation data measured in magnetic fields of up to 60 T show several oscillation frequencies exhibiting low effective masses, indicating the presence of Dirac-like band dispersion in \ce{SrCu4As2}, as suggested by the band structure calculations.

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Sudip Malick, Michał J. Winiarski, Joanna Bławat, Hanna Świątek, John Singleton, Tomasz Klimczuk. 2025-10-16. Quantum oscillations and transport properties of layered single-crystal SrCu$_4$As$_2$. https://doi.org/10.1103/tc3c-lzcr

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