title: Mechano-electronic superlattices in silicon nanoribbons.
abstract: Significant new mechanical and electronic phenomena can arise in single-crystal semiconductors when their thickness reaches nanometer dimensions, where the two surfaces of the crystal are physically close enough to each other that what happens at one surface influences what happens at the other. We show experimentally that, in silicon nanomembranes, through-membrane elastic interactions cause the double-sided ordering of epitaxially grown nanostressors that locally and periodically highly strains the membrane, leading to a strain lattice. Because strain influences band structure, we create a periodic band gap modulation, up to 20% of the band gap, effectively an electronic superlattice. Our calculations demonstrate that discrete minibands can form in the potential wells of an electronic superlattice generated by Ge nanostressors on a sufficiently thin Si(001) nanomembrane at the temperature of 77 K. We predict that it is possible to observe discrete minibands in Si nanoribbons at room temperature if nanostressors of a different material are grown.
authors.affiliation: Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Minghuang
authors.initials: M
authors.lastname: Huang
authors.forename: Clark S
authors.initials: CS
authors.lastname: Ritz
authors.forename: Bozidar
authors.initials: B
authors.lastname: Novakovic
authors.forename: Decai
authors.initials: D
authors.lastname: Yu
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Frank
authors.initials: F
authors.lastname: Flack
authors.forename: Donald E
authors.initials: DE
authors.lastname: Savage
authors.forename: Paul G
authors.initials: PG
authors.lastname: Evans
authors.forename: Irena
authors.initials: I
authors.lastname: Knezevic
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.forename: Max G
authors.initials: MG
authors.lastname: Lagally