Coexistence of Bloch electrons and glassy electrons in Ca10(Ir4As8)(Fe2_xIrxAs2)5 revealed by angle-resolved photoemission spectroscopy

TL;DR

This study reveals a unique electronic state in Ca10(Ir4As8)(Fe2_xIrxAs2)5 where well-defined Bloch electrons coexist with glassy, disordered electrons, highlighting complex interlayer interactions in this material.

Contribution

It demonstrates the coexistence of Bloch and glassy electrons in a single compound, providing new insights into layered electronic systems.

Findings

Fe 3d electrons form typical Fermi pockets in FeAs layer

Ir 5d electrons are metallic and glassy due to disorder

Coexistence of Bloch and glassy electrons in the material

Abstract

Angle-resolved photoemission spectroscopy of Ca10(Ir4As8)(Fe2_xIrxAs2)5 shows that the Fe 3d electrons in the FeAs layer form the hole-like Fermi pocket at the zone center and the electron-like Fermi pockets at the zone corners as commonly seen in various Fe-based superconductors. The FeAs layer is heavily electron doped and has relatively good two dimensionality. On the other hand, the Ir 5d electrons are metallic and glassy probably due to atomic disorder related to the Ir 5d orbital instability. Ca10(Ir4As8)(Fe2_xIrxAs2)5 exhibits a unique electronic state where the Bloch electrons in the FeAs layer coexist with the glassy electrons in the Ir4As8 layer.