Growth and Electronic Structure Studies of Metal Intercalated Transition Metal Dichalcogenides MxNbSe2 (M: Fe and Cu)

There has been renewed interest in transition metal dichalcogenides (TMDs) as electronic materials. The modification of the electronic structures of TMDs by means of metal intercalation would be of interest in that respect. With this motivation, we have synthesized and performed angle-resolved photoemission studies on Fe- and Cu-intercalated TMD FexNbSe2 and CuxNbSe2 with various x values. FexNbSe2 (x = 0, 0.25) and CuxNbSe2 (x = 0, 0.06) were grown by the iodine vapor transport method. Intercalation and doping were confirmed by changes in c-axis lattice constant and electronic structure, respectively. A significant amount of electron doping from Fe and Cu was observed, as indicated in the ARPES data measured as the rigid downshift of bands. In addition, band folding was observed in FexNbSe2, for which the unit cell is doubled owing to the Fe order. However, the extra band folding expected from the antiferromagnetic order of Fe was not observed. (C) 2013 The Japan Society of Applied Physics