摘要
The three-dimensional electronic structure and the nature of Ce 4f electrons of the Kondo insulator CeRu_(4)Sn_(6)are investigated by angle-resolved photoemission spectroscopy,utilizing tunable photon energies.Our results reveal(i)the three-dimensional k-space nature of the Fermi surface,(ii)the localized-to-itinerant transition of f electrons occurs at a much high temperature than the hybridization gap opening temperature,and(iii)the“relocalization”of itinerant f-electrons below 25 K,which could be the precursor to the establishment of magnetic order.
基金
supported by the National Natural Science Foundation of China(Grant Nos.12074436 and 11574402)
the Science and Technology Innovation Program of Hunan Province(No.2022RC3068)
the open project of Beijing National Laboratory for Condensed Matter Physics(Grant No.ZBJ2106110017).