title: Accurate Nanoscale Crystallography in Real-Space Using Scanning Transmission Electron Microscopy.
abstract: Here, we report reproducible and accurate measurement of crystallographic parameters using scanning transmission electron microscopy. This is made possible by removing drift and residual scan distortion. We demonstrate real-space lattice parameter measurements with <0.1% error for complex-layered chalcogenides Bi2Te3, Bi2Se3, and a Bi2Te2.7Se0.3 nanostructured alloy. Pairing the technique with atomic resolution spectroscopy, we connect local structure with chemistry and bonding. Combining these results with density functional theory, we show that the incorporation of Se into Bi2Te3 causes charge redistribution that anomalously increases the van der Waals gap between building blocks of the layered structure. The results show that atomic resolution imaging with electrons can accurately and robustly quantify crystallography at the nanoscale.
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: J Houston
authors.initials: JH
authors.lastname: Dycus
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Harris
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Xiahan
authors.initials: X
authors.lastname: Sang
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Chris M
authors.initials: CM
authors.lastname: Fancher
authors.affiliation: 2School of Physics and Astronomy,Monash University, Clayton,VIC 3800,Australia.
authors.forename: Scott D
authors.identifier: http://orcid.org/0000-0003-4862-4827
authors.initials: SD
authors.lastname: Findlay
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Adedapo A
authors.initials: AA
authors.lastname: Oni
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Tsung-Ta E
authors.initials: TT
authors.lastname: Chan
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Carl C
authors.initials: CC
authors.lastname: Koch
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Jacob L
authors.initials: JL
authors.lastname: Jones
authors.affiliation: 3School of Physics,University of Melbourne,Parkville,VIC 3010,Australia.
authors.forename: Leslie J
authors.initials: LJ
authors.lastname: Allen
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Irving
authors.affiliation: 1Department of Materials Science and Engineering,North Carolina State University,Raleigh,NC 27695,USA.
authors.forename: James M
authors.initials: JM
authors.lastname: LeBeau
keywords: Bi2Te3; atomic resolution spectroscopy; nanoscale metrology; scanning transmission electron microscopy