4.6 Article

Magnetic surface reconstruction in the van der Waals antiferromagnet Fe1+xTe

Journal

PHYSICAL REVIEW B
Volume 103, Issue 2, Pages -

Publisher

AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.103.024406

Keywords

-

Funding

  1. EPSRC [EP/R031924/1, EP/R032130/1]
  2. NIST Center for Neutron Research
  3. Austrian Science Fund (FWF) [P32144-N36]
  4. VSC4 of the Vienna University of Technology
  5. EPSRC [EP/R031924/1, EP/R032130/1] Funding Source: UKRI
  6. Austrian Science Fund (FWF) [P32144] Funding Source: Austrian Science Fund (FWF)

Ask authors/readers for more resources

Fe1+xTe is a two-dimensional van der Waals antiferromagnet that becomes superconducting with anion substitution on the Te site. The bulk magnetic structure of Fe1+xTe shows collinear in-plane order, while the surface exhibits a magnetic surface reconstruction with a canting angle of the spins. This difference in magnetic properties between the bulk and surface of Fe1+xTe suggests that surface structural relaxation leads to an out-of-plane magnetocrystalline anisotropy.
Fe1+xTe is a two-dimensional van der Waals antiferromagnet that becomes superconducting on anion substitution on the Te site. The properties of the parent phase of Fe1+xTe are sensitive to the amount of interstitial iron situated between the iron-tellurium layers. Fe1+xTe displays collinear magnetic order coexisting with low-temperature metallic resistivity for small concentrations of interstitial iron x and helical magnetic order for large values of x. While this phase diagram has been established through scattering [see, for example, E. E. Rodriguez et al., Phys. Rev. B 84, 064403 (2011); S. Rossler et al., ibid. 84, 174506 (2011)], recent scanning tunneling microscopy measurements [C. Trainer et al., Sci. Adv. 5, eaav3478 (2019)] have observed a different magnetic structure for small interstitial iron concentrations x with a significant canting of the magnetic moments along the crystallographic c axis of theta = 28 degrees +/- 3 degrees. In this paper, we revisit themagnetic structure of Fe1.09Te using spherical neutron polarimetry and scanning tunneling microscopy to search for this canting in the bulk phase, and we compare surface and bulk magnetism. The results show that the bulk magnetic structure of Fe1.09Te is consistent with collinear in-plane order (theta = 0 with an error of similar to 5 degrees). Comparison with scanning tunneling microscopy on a series of Fe1+xTe samples reveals that the surface exhibits a magnetic surface reconstruction with a canting angle of the spins of theta = 29.8 degrees. We suggest that this is a consequence of structural relaxation of the surface layer resulting in an out-of-plane magnetocrystalline anisotropy. The magnetism in Fe1+xTe displays different properties at the surface when the symmetry constraints of the bulk are removed.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.6
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available