title: Structure of Co-2 × 2 nanoislands grown on Ag/Ge(111)-√3 × √3 surface studied by scanning tunneling microscopy.
abstract: We have found that Co-2 × 2 islands grown on an Ag/Ge(111)-√3 × √3 surface have hcp structure with the (11-20) orientation. The island evolution involves transformation of the unit cell shape from parallelogram into rectangular, which is accompanied by the island shape transformation from hexagonal into stripe-like. Identified are two crystallographic directions for the island growth, the pseudo-[0001] and the pseudo-[1-100]. We have observed the occurrence of a lateral shift between the topmost and the underlying bilayers in the case of the island growth along the pseudo-[0001] direction. In contrast, the topmost and the underlying bilayers are unshifted for the growth along the pseudo-[1-100] direction.
authors.affiliation: Department of Physics, National Taiwan Normal University, 88, Sec, 4 Ting-Chou Rd,, Taipei, 116, Taiwan, Republic of China. phtifu@phy.ntnu.edu.tw.
authors.forename: Xiao-Lan
authors.initials: XL
authors.lastname: Huang
authors.forename: Chun-Liang
authors.initials: CL
authors.lastname: Lin
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Tomaszewska
authors.forename: Chun-Rong
authors.initials: CR
authors.lastname: Chen
authors.forename: Tsu-Yi
authors.initials: TY
authors.lastname: Fu