Simulation of inhomogeneous strain in Ge-Si core-shell nanowires

  • Yuhui He
  • Yuning Zhao
  • Chun Fan
  • Xiaoyan Liu
  • Ruqi Han
Research Article


This paper studies the elastic deformation field in lattice-mismatched Ge-Si core-shell nanowires (NWs). Infinite wires with a cylindrical cross section under the assumption of translational symmetry are considered. The strain distributions are found by minimizing the elastic energy per unit cell using finite element method. This paper finds that the trace of the strain is discontinuous with a simple, almost piecewise variation between core and shell, whereas the individual components of the strain can exhibit complex variations. The simulation results are prerequisite of strained band structure calculation, and pave a way for further investigation of strain effect on the related transport property simulation.


core-shell nanowire strain continuum elasticity 


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Copyright information

© Higher Education Press and Springer-Verlag GmbH 2009

Authors and Affiliations

  • Yuhui He
    • 1
  • Yuning Zhao
    • 1
  • Chun Fan
    • 2
  • Xiaoyan Liu
    • 1
  • Ruqi Han
    • 1
  1. 1.Institute of MicroelectronicsPeking UniversityBeijingChina
  2. 2.Computer Center of Peking UniversityBeijingChina

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