Two-Dimensional Magnetism in Rare Earth Silicides

Two‐dimensional magnetism in rare earth silicides encompasses a class of materials in which layers or ultrathin films of compounds formed between silicon and rare earth elements exhibit long‐range magnetic order within a single atomic plane. The combination of localized 4f electrons, strong spin–orbit coupling and reduced dimensionality gives rise to exotic magnetic ground states that are robust against thermal fluctuations. In contrast to bulk rare earth magnets, two‐dimensional silicide layers can manifest ferromagnetic or antiferromagnetic order at elevated temperatures due to pronounced magnetic anisotropy, overcoming the limitations set by the Mermin–Wagner theorem. The layered nature and chemical compatibility with silicon technology make these materials promising for spintronic devices, non‐volatile memory elements and quantum information platforms. Recent advances have demonstrated tunable magnetic transition temperatures, control of coercivity via external fields, and integration with two‐dimensional conductors. The global significance of this research lies in the potential for atomically thin magnetic components that can be directly integrated into existing semiconductor architectures, opening avenues for multifunctional nanoscale devices that combine logic, storage and sensing within a single platform.

Research from Nature Portfolio

Recent studies have employed a bottom‐up synthesis of silicene layers functionalised by rare earth atoms, revealing an evolution from bulk antiferromagnetism to intrinsic in‐plane ferromagnetism in monolayer films. The emerging ferromagnetic order is detected through magneto‐optical Kerr measurements and manifests in characteristic anomalies in electron transport at the transition temperature. Complementary high‐resolution scanning tunnelling microscopy of self-assembled gadolinium silicide nanowires has resolved atomic structures that vary systematically with wire width. These observations underpin new structural models that link the two‐dimensional silicide lattice to one‐dimensional wire geometries, offering a route to tailor local magnetic exchange interactions and electronic band dispersions within an epitaxial framework.

Two-Dimensional Magnetism in Rare Earth Silicides publication trend

The graph below shows the total number of articles in two-dimensional magnetism in rare earth silicides across all publications each year (not limited to Nature Index journals).

Technical terms

Rare-earth silicide: A compound of a rare earth element and silicon forming layered structures with magnetic 4f electrons.

Two-dimensional ferromagnetism: Long-range magnetic order confined to a single atomic layer.

Magnetic anisotropy: Directional dependence of magnetic properties within a material.

Spin–orbit coupling: Interaction between an electron’s spin and its orbital motion around the nucleus.

Monolayer: A single atom- or molecule-thick layer of material.

References

1. Unveiling the stacking-dependent electronic properties of the 2D ultrathin rare-earth metalloxenes family LnX 2 (Ln = Eu, Gd, Dy; X = Ge, Si). Journal of Materials Chemistry C (2024).
2. Emerging two-dimensional ferromagnetism in silicene materials. Nature Communications (2018).
3. Spectroscopic Analysis of Rare-Earth Silicide Structures on the Si(111) Surface. Materials (2021).
4. Atomic structures of self-assembled epitaxially grown GdSi2 nanowires on Si(001) by STM. Scientific Reports (2019).