Quasiparticle Mass Enhancement and Temperature Dependence of the Electronic Structure of Ferromagnetic SrRuO3 Thin Films

TL;DR

This study uses high-resolution photoemission to analyze the electronic structure of SrRuO3 thin films, revealing quasiparticle behavior, mass enhancement, and the role of local moments in its ferromagnetism.

Contribution

First detailed ARPES investigation of SrRuO3 thin films showing quasiparticle dynamics and temperature effects on electronic structure.

Findings

Well-defined quasiparticles in ferromagnetic state

Strong coupling to low-energy bosonic modes

Quasiparticle coherence decreases above Curie temperature

Abstract

We report high-resolution angle-resolved photoemission studies of epitaxial thin films of the correlated 4d transition metal oxide ferromagnet SrRuO3. The Fermi surface in the ferromagnetic state consists of well-defined Landau quasiparticles, exhibiting strong coupling to low-energy bosonic modes which contributes to the large effective masses observed by transport and thermodynamic measurements. Upon warming the material through its Curie temperature, we observe a substantial decrease in quasiparticle coherence, but negligible changes in the ferromagnetic exchange splitting, suggesting that local moments play an important role in the ferromagnetism in SrRuO3.