Strain distribution of confined Ge/GeO2 core/shell nanoparticles engineered by growth environments

Highlights: • The strains of the Ge core and the GeO₂ shell strongly depend on the growth environments of the nanoparticles. • There has a transformation of the strain on Ge core from tensile to compressive strain during the growth of Ge/GeO₂ core/shell nanoparticles. • The transformation of the strain is closely related with the Young's modulus of surrounding materials of Ge/GeO₂ core/shell nanoparticles. • These findings pave the way for tuning the strain of confined Ge/GeO₂ core/shell nanoparticles with the variation of growth environments. The strain distributions of Ge/GeO₂ core/shell nanoparticles confined in different host matrix grown by surface oxidation are investigated. The simulated results by finite element method demonstrated that the strains of the Ge core and the GeO₂ shell strongly depend on the growth environments of the nanoparticles. Moreover, it can be found that there is a transformation of the strain on Ge core from tensile to compressive strain during the growth of Ge/GeO₂ core/shell nanoparticles. And, the transformation of the strain is closely related with the Young's modulus of surrounding materials of Ge/GeO₂ core/shell nanoparticles.