title: Electronic phase diagram of single-element silicon "strain" superlattices.
abstract: The evidence that the band gap of Si changes significantly with strain suggests that by alternating regions of strained and unstrained Si one creates a single-element electronic heterojunction superlattice (SL), with the carrier confinement defined by strain rather than by the chemical differences in conventional compositional SLs. Using first-principles calculations, we map out the electronic phase diagram of a one-dimensional pure-silicon SL. It exhibits a high level of phase tunability, e.g., tuning from type I to type II. Our theory rationalizes a recent observation of a strain SL in a Si nanowire and provides general guidance for the fabrication of single-element strain SLs.
authors.affiliation: Institute for Advanced Study, Tsinghua University, Beijing, China, 100084.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.forename: Wenhui
authors.initials: W
authors.lastname: Duan
authors.forename: Max G
authors.initials: MG
authors.lastname: Lagally
authors.forename: Feng
authors.initials: F
authors.lastname: Liu