Strain distribution in zincblende and wurtzite GaAs nanowires bent by a one-sided (In, Al)As shell: Consequences for torsion, chirality, and piezoelectricity
Authors
- Hadjimichael, Yiannis
ORCID: 0000-0003-3517-8557 - Brandt, Oliver
ORCID: 0000-0002-9503-5729 - Merdon, Christian
ORCID: 0000-0002-3390-2145 - Manganelli, Costanza
- Farrell, Patricio
ORCID: 0000-0001-9969-6615
2020 Mathematics Subject Classification
- 74B20
2010 Physics and Astronomy Classification Scheme
- 62.23Hj, 68.65.-k, 62.20.-x, 77.84.-s, 77.65.Ly
Keywords
- Bent nanowires, semiconductor heterostructures, strain engineering, torsion, piezoelectricity
DOI
Abstract
We present a finite-strain model that is capable of describing the large deformations in bent nanowire heterostructures. The model incorporates a nonlinear strain formulation derived from the first Piola-Kirchhoff stress tensor, coupled with an energy functional that effectively captures the lattice-mismatch-induced strain field. We use the finite element method to solve the resulting partial differential equations and extract cross- sectional maps of the full strain tensor for both zincblende and wurtzite nanowires with lattice-mismatched core and one-sided stressor shell. In either case, we show that the bending is essentially exclusively determined by $varepsilonzz$. However, the distinct difference in shear strain has important consequences with regard to both the mechanical deformation and the existence of transverse piezoelectric fields in the nanowires.
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