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arXiv · 2511.07079

Effect of uniaxial stress on helimagnetic phases in the square-lattice itinerant magnet EuAl$_{4}$

Masaki Gen·Takuya Nomoto·Hiraku Saito·Taro Nakajima·Yusuke Tokunaga·Rina Takagi·Shinichiro Seki·Taka-hisa Arima
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Abstract

We investigate uniaxial-stress effects on the magnetic phase diagram of the square-lattice itinerant magnet EuAl$_{4}$, where strong coupling among spin, lattice, and charge produces a variety of helimagnetic phases, including rhombic and square skyrmion lattices. Combining resistivity and magnetization measurements with neutron scattering, we find that compressive stresses of only several tens of megapascal along [010] enhance antiferromagnetic character and shorten the magnetic modulation period in the lowest-temperature single-Q spiral state, thereby driving the critical temperatures and fields of multiple phases to higher values. First-principles calculations show that increasing orthorhombic lattice distortion deforms the Fermi surface relevant to the magnetism, providing compelling evidence that Fermi-surface nesting plays a crucial role in stabilizing the helical magnetic modulations in EuAl$_{4}$.

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Masaki Gen, Takuya Nomoto, Hiraku Saito, Taro Nakajima, Yusuke Tokunaga, Rina Takagi, Shinichiro Seki, Taka-hisa Arima. 2025-11-10. Effect of uniaxial stress on helimagnetic phases in the square-lattice itinerant magnet EuAl$_{4}$. https://doi.org/10.1103/frqw-vng9

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