Domain Resolved nano-ARPES Study on Orbital Ordered Phase of Transition-metal Compounds

Abstract

Angle-resolved photoemission spectromicroscopy with submicron resolution (nano-ARPES) is a powerful technique to study electronic structure of microcrystals and microdomains. Transition-metal compounds such as FeTe and IrTe₂ exhibit unique phase transitions due to orbital symmetry breaking (orbital order). In nano-ARPES studies on FeTe and IrTe₂ surface, we observed interesting domain textures which would be related to their microscopic orbital orders. The antiferromagnetic phase of FeTe hosts stripe-type domains driven by its anisotropic electronic state. In case of IrTe₂, each domain harbors quasi one-dimensional surface bands forming fragmented Fermi surfaces (Fermi arcs). The nano-ARPES measurement enabled us to identify the unique domain dependent surface states in the orbital ordered phase of IrTe₂.