Mapping of Strain Fields in GaAs/GaAsP Core-Shell Nanowires with Nanometer Resolution

TitleMapping of Strain Fields in GaAs/GaAsP Core-Shell Nanowires with Nanometer Resolution
Publication TypeJournal Article
Year of Publication2015
AuthorsJones, EJ, Ermez, S, Gradecak, S
JournalNano Letters
Volume15
Issue12
Pagination7873 - 7879
Date Published2015/12//
Abstract

We report the nanoscale quantification of strain in GaAs/GaAsP core-shell nanowires. By tracking the shifting of higher-order Laue zone (HOLZ) lines in convergent beam electron diffraction patterns, we observe unique variations in HOLZ line separation along different facets of the core-shell structure, demonstrating the nonuniform strain fields created by the heterointerface. Furthermore, through the use of continuum mechanical modeling and Bloch wave analysis we calculate expected HOLZ line shift behavior, which are directly matched to experimental results. This comparison demonstrates both the power of electron microscopy as a platform for nanoscale strain characterization and the reliability of continuum models to accurately calculate complex strain fields in nanoscale systems.