Hybridization Effects in CeCoIn\(_5\) Studied by Angle-resolved Photoemission Spectroscopy

We studied the electronic structure of a canonical heavy fermion superconductor CeCoIn\(_5\) using angle-resolved photoelectron spectroscopy (ARPES). We observed a non-uniform distribution of \(4f\)-derived spectral weight across the Fermi surface map measured below the coherence temperature (\(T=6~K < T_coh≈ 45\) K). Different effects of the coupling between \(4f\)-states and conduction bands were observed near the Fermi level (\(E_F\)): (i) rapid change of the band slope and increasing \(4f\) spectral contribution, when approaching \(E_F\), (ii) presence of heavy quasiparticle bands (\(m~ 100m_e\)). Abstract Published by the Jagiellonian University 2026 authors