Effects of Ge/Sb Intermixing on the Local Structures and Optical Properties of GeTe–Sb2Te3 Superlattice

  • Gang Han
  • Furong LiuEmail author
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


GeTe–Sb2Te3-based superlattice (GST-SL) is a new phase change film prepared with alternative GeTe and Sb2Te3 layers, known as interfacial phase-change material, showing strongly improved switching properties. However, the recent experiments showed that Ge/Sb atomic intermixing was hardly to be avoided and would influence the phase change process. In this paper, the effects of Ge/Sb atomic intermixing on the local structure and phase change mechanism were investigated by first-principles simulations. The free energy evolution with temperatures indicated that Ge/Sb intermixing is helpful for phase change. The bond analysis and local order parameter showed that no obvious structure changes happened when lower than 1200 K, and there were almost no fourfold Ge-tetrahedral structures even when quenched from 1500 K, different from the traditional GST materials. The Ge/Sb intermixing and its ratios can not only influence the structural transition, but also play a vital role on the optical properties. These findings enrich a deep understanding of Ge/Sb intermixing on GST-SL phase changes.


Intermixing First-principles simulation Local structure Optical properties Phase change mechanism 



This work is supported by the Beijing Natural Science Foundation-Municipal Education Committee Joint Funding Project (KZ201910005004).

Conflicts of Interest

The authors declare no competing financial interest.


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Copyright information

© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  1. 1.Institute of Laser Engineering, Beijing University of TechnologyBeijingChina
  2. 2.Beijing Engineering Research Center of Applied Laser TechnologyBeijing University of TechnologyBeijingChina

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