STM Investigation of Surface Reconstruction of FeSn

Recently kagome compounds attract lots of research interest due to the flat bands, Dirac fermion and the strong electronic correlation due to the kagome lattice[1-4]. However, there is a lack of study of the surface stability of kagome lattice against high temperature. In this talk, we present the study of the surface reconstruction of kagome Fe3Sn layer of antiferromagnetic metal FeSn with scanning tunneling microscope (STM). We heat FeSn to a series of temperatures below room temperature and investigate the surface morphology evolution. Our results shed light on the stability of kagome surface and thermodynamics of defect formation.