Reorientation of the diagonal double-stripe spin structure at Fe<sub>1+y</sub>Te bulk and thin-film surfaces.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28059102.
- Also identified by DOI 10.1038/ncomms13939 and PMC identifier 5227097.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Establishing the relation between ubiquitous antiferromagnetism in the parent compounds of unconventional superconductors and their superconducting phase is important for understanding the complex physics in these materials. Going from bulk systems to thin films additionally affects their phase diagram. For Fe<sub>1+y</sub>Te, the parent compound of Fe<sub>1+y</sub>Se<sub>1-x</sub>Te<sub>x</sub> superconductors, bulk-sensitive neutron diffraction revealed an in-plane oriented diagonal double-stripe antiferromagnetic spin structure. Here we show by spin-resolved scanning tunnelling microscopy that the spin direction at the surfaces of bulk Fe<sub>1+y</sub>Te and thin films grown on the topological insulator Bi<sub>2</sub>Te<sub>3</sub> is canted out of the high-symmetry directions of the surface unit cell resulting in a perpendicular spin component, keeping the diagonal double-stripe order. As the magnetism of the Fe d-orbitals is intertwined with the superconducting pairing in Fe-based materials, our results imply that the superconducting properties at the surface of the related superconducting compounds might be different from the bulk.