Revision 1

Superseded · first revision · record

Title: What stabilizes skyrmion lattices in centrosymmetric magnets like Gd2PdSi3?
Plain: Most skyrmions appear in crystals lacking mirror symmetry, where a twisting interaction favors them. Gd2PdSi3 and GdRu2Si2 have that symmetry yet host very small skyrmions, and the competing explanations involve geometric frustration or interactions carried by conduction electrons.
Precise: For Gd2PdSi3 (triangular) and GdRu2Si2 (tetragonal), with skyrmion-lattice periods of about 2 to 3 nm, determine which mechanism stabilizes the multi-$q$ state: frustrated RKKY couplings, Fermi-surface-driven biquadratic and four-spin interactions, or dipolar and anisotropy effects. An answer is a microscopic model derived from the measured band structure that reproduces the field-temperature phase diagram and the modulation vectors.
Settled by: Ab initio spin models compared with resonant x-ray and neutron data over the full phase diagram, plus pressure or doping tuning of the Fermi surface.
Kind: phenomenon
Answer type: mechanism
References: (empty)
Literature status: contested
Status note: (empty)
Posed since: 2019