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arXiv · 2603.08524

Collinear spin density wave state in distorted square-lattice GdNiSn$_4$

Charles C. Tam·Sarah Schwarz·Xin Zhang·Sudipta Chatterjee·Scott B. Lee·Rebecca Scatena·Leslie M. Schoop·Stephen D. Wilson
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Abstract

We characterize the magnetic ground state of the newly synthesized lanthanide intermetallic GdNiSn$_4$ via resonant elastic x-ray scattering measurements. This compound forms distorted square nets of Gd that initially order magnetically below 23 K followed by a lower temperature transition at 16 K. Our scattering data identify the ground state order as a single-$q$ incommensurate, collinear order that slides towards a commensurate wave vector above the 16 K transition. Magnetic symmetry analysis combined with azimuthal dependence resolves the ground state magnetic structure as a moment-modulated spin density wave state with Gd moments oriented parallel to the in-plane a-axis. We discuss connections between the observed magnetic order and electronic properties in this square-net compound.

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Charles C. Tam, Sarah Schwarz, Xin Zhang, Sudipta Chatterjee, Scott B. Lee, Rebecca Scatena, Leslie M. Schoop, Stephen D. Wilson. 2026-03-09. Collinear spin density wave state in distorted square-lattice GdNiSn$_4$. https://doi.org/10.1103/2plq-5mql

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