Abstract
We report a neutron diffraction study of the magnetic structure of CeAlGe, a candidate topological semimetal that hosts a noncollinear, multi-k magnetic phase. By measuring both low- and high-momentum-transfer magnetic Bragg peaks within a single experimental setup, we refine a magnetic structure model based solely on localized Ce moments. This model, which differs from that obtained using only high-Q data, quantitatively reproduces the observed intensities, including the (000) zeroth-order magnetic satellites that are especially sensitive to subtle components of the modulation. While a contribution from itinerant electrons to the zeroth satellite cannot be definitively excluded, our analysis reveals no unambiguous evidence for such effects within experimental uncertainty. The refined magnetic structures exhibit topologically nontrivial winding patterns, derived from the fitted magnetic parameters, that support localized, particle-like spin textures with half-integer topological charges. These features provide a natural microscopic origin for the observed topological Hall effect, establishing CeAlGe as a model system where magnetism and topology are intimately linked.
| Original language | English |
|---|---|
| Journal | Physical Review B |
| Volume | 112 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 29 2025 |
Funding
This research utilized resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by Oak Ridge National Laboratory. The beam time was allocated to CNCS on Proposal No. IPTS-24824. S.S. acknowledges support from Swiss National Science Foundation (SNSF) through project grant 188706. Part of this work was performed at the Swiss Spallation Neutron Source (SINQ), Paul Scherrer Institut (PSI), Villigen, Switzerland. We gratefully acknowledge valuable contributions from Naoya Kanazawa, Victor Ukleev, Dariusz J. Gawryluk, Jun-zhang Ma, Muntaser Naamneh, Nicholas C. Plumb, Lukas Keller, and Robert Cubitt, as recognized in our previous study [1].