Polaron-formation revealed by transient XUV imaginary refractive index changes in different iron compounds

Abstract

We use transient extreme ultraviolet (XUV) reflection absorption spectroscopy to study polaron formation on hematite and akaganeite surfaces. We observed a reduction in the offset of the imaginary refractive index (κ_offset) that was attributed to the photoemission cross-section. The difference in the κ_offset reduction indicated that deeper-trapped polarons were formed in hematite than in akaganeite.