Nature of the bad metallic behavior of Fe_{1.06}Te inferred from its evolution in the magnetic state

TL;DR

This study uses angle-resolved photoelectron spectroscopy to explore the electronic and magnetic transitions in Fe_{1.06}Te, revealing unusual metallic behavior linked to spin fluctuations and correlations, distinct from iron-pnictides.

Contribution

It provides new insights into the electronic structure evolution and magnetic transition in Fe_{1.06}Te, highlighting the role of spin fluctuations and correlations in its bad metallic behavior.

Findings

AFM state is a good metal with a well-defined Fermi surface.

PM state exhibits a large pseudogap on the electron pocket.

The evolution differs from iron-pnictides due to absence of nesting.

Abstract

We investigate with angle resolved photoelectron spectroscopy the change of the Fermi Surface (FS) and the main bands from the paramagnetic (PM) state to the antiferromagnetic (AFM) occurring below 72 K in Fe_{1.06}Te. The evolution is completely different from that observed in iron-pnictides as nesting is absent. The AFM state is a rather good metal, in agreement with our magnetic band structure calculation. On the other hand, the PM state is very anomalous with a large pseudogap on the electron pocket that closes in the AFM state. We discuss this behavior in connection with spin fluctuations existing above the magnetic transition and the correlations predicted in the spin-freezing regime of the incoherent metallic state.