Experimental determination of the interacting Fermi-surface structure

Determine experimentally the renormalized Fermi-surface structure of stoichiometric FeTe that controls the presence and locations of superconducting nodes.

Background

The mean-field calculations produce either a d-wave or nodal s-wave state over broad parameter ranges. However, the location and even detailed structure of the nodes depend on the underlying interaction-renormalized Fermi surface.

The paper does not provide an experimental determination of this Fermi-surface structure, limiting the ability to distinguish among the theoretically allowed nodal configurations.

References

The presence and location of the nodes depend on details of the underlying Fermi surface, which has not yet been experimentally determined.

— Signatures of nodal superconductivity in stoichiometric FeTe  (2609.08116 - Li et al., 8 Sep 2026) in Section 4, paragraph beginning “We perform self-consistent mean-field calculations”

Thus, while the present results do not distinguish between $d$- and $s$-wave states, they establish nodal superconductivity as a robust outcome across different parameter regimes.

— Signatures of nodal superconductivity in stoichiometric FeTe  (2609.08116 - Li et al., 8 Sep 2026) in Section 4, final paragraph