2024-03-28T16:22:37Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/683792022-11-17T02:08:08Zhdl_2115_20053hdl_2115_145Direct observation of subsurface charge ordering in Fe3O4(001) by scanning tunneling microscopy/spectroscopyHiura, SatoshiIkeuchi, AkiraJochi, MasafumiYamazaki, RikuTakahashi, SotaroSubagyo, AgusMurayama, AkihiroSueoka, Kazuhisa428In this study, we characterized Fe3O4(001) films using scanning tunneling microscopy/spectroscopy (STM/STS). On the film surfaces, individual iron atoms and (root 2 x root 2)R45 degrees reconstructed structures were observed by STM. The STS results showed that the local density of states just below the Fermi level was higher in narrow sections than in wide sections of the surface reconstruction perpendicular to the iron rows. Periodic density of states modulations reproducing this electronic structure were clearly observed in the differential tunneling conductance map. These experimental results revealed the presence of subsurface charge ordering of Fe2+-Fe2+ and Fe3+-Fe3+ dimers, as proposed in previous density functional theory studies.IOP PublishingJournal Articleapplication/pdfhttp://hdl.handle.net/2115/68379https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/68379/1/APEX_HokkaidoUniv_Hiura.pdf1882-0778Applied Physics Express (APEX)104457012017-04enginfo:doi/10.7567/APEX.10.045701© 2017 The Japan Society of Applied Physicsauthor