Strong rashba effect and different f−d hybridization phenomena at the surface of the heavy-fermion superconductor CeIrIn5

New temperature scales and remarkable differences from bulk properties have increasingly placed the surfaces of strongly correlated f materials into the focus of research activities. Applying first-principles calculations and angle-resolved photoelectron spectroscopy measurements, a strong Rashba effect and spin-split surface states at the CeIn surface of the heavy-fermion superconductor CeIrIn5 are revealed. The unveiled 4f-derived electron landscape is remarkably distinct for surface and bulk Ce implying the existence of novel temperature scales near the surface region in this material. These results show that ab initio calculations can reliably predict the unusual electronic and spin structure of surfaces of strongly correlated 4f systems where Rashba spin-orbit-coupling phenomena emerge. It is suggested that the structural blocks of such materials can be combined with magnetically active layers for engineering of novel nanostructural objects with appropriate substrates where the diversity of f-driven properties can be applied for the development of novel functionalities.This work was supported by the German Research Foundation (DFG) through Grants No. KR3831/5-1, No. LA655/20-1, No. SFB1143 (Project No. 247310070), and No. 0519ODR. The authors acknowledge support from the Russian Foundation for Basic Research (Grant No. 20-32-70127) and Saint-Petersburg State University (Grant No. ID 73028629). The authors acknowledge MAX IV Laboratory for time on Beamline Bloch under Proposal 20200640. Research conducted at MAX IV, a Swedish national user facility, was supported by the Swedish Research council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496. The authors acknowledge support from a government research assignment for ISPMS SB RAS (Project FWRW-2019-0032).Peer reviewe