Counterintuitive strain distribution in axial (In,Ga)N/GaN nanowires

Autor: Krause, Thilo, Hanke, Michael, Brandt, Oliver, Trampert, Achim
Rok vydání: 2016
Předmět:
Zdroj: APL 108, 032103 (2016)
Druh dokumentu: Working Paper
DOI: 10.1063/1.4940053
Popis: We study the three-dimensional deformation field induced by an axial (In,Ga)N segment in a GaN nanowire. Using the finite element method within the framework of linear elasticity theory, we study the dependence of the strain field on the ratio of segment length and nanowire radius. Contrary to intuition, the out-of-plane-component of the elastic strain tensor is found to assume large negative values for a length-to-radius ratio close to one. We show that this unexpected effect is a direct consequence of the deformation of the nanowire at the free sidewalls and the associated large shear strain components. Simulated reciprocal space maps of a single (In,Ga)N/GaN nanowire demonstrate that nanofocus x-ray diffraction is a suitable technique to assess this peculiar strain state experimentally.
Databáze: arXiv