Microscopic origin of zero-field magnetic textures

Identify the microscopic source and through-film location of the weak magnetic textures observed in stoichiometric FeTe above the superconducting transition temperature.

Background

Weak magnetic textures are observed in zero-field scanning SQUID images of sample A. Their stray-field amplitudes are much smaller than those of isolated superconducting vortices, they persist to 25 K, and they show no clear spatial correlation with the diamagnetic response.

The measurements establish that these textures are not evidently associated with superconductivity, but they do not determine whether the signals originate at the surface, within the FeTe film, at the substrate interface, or from another microscopic magnetic source.

References

The origin of these magnetic textures remains unknown. In particular, our measurements do not determine where within the film the magnetic signals originate or the microscopic source of the magnetism. Further studies are needed to clarify their origin.

— Signatures of nodal superconductivity in stoichiometric FeTe  (2609.08116 - Li et al., 8 Sep 2026) in Supplementary Information, Section “Images of vortices and background field compensation”