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Effect of vacancy disorder in phase-change materials
Young-Sun Song1, Seung-Hoon Jhi1
1Department of Physics, Pohang University of Science and Technology, Pohang 37673, Republic of Korea.
Summary
Phase-change materials (PCMs) have disordered vacancies affecting properties. This study links vacancy distribution to bonding networks, enabling prediction of material characteristics like energy and charge localization.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Materials Science
Background:
- Ge-Sb-Te-based phase-change materials (PCMs) exhibit tunable electrical and optical properties.
- These properties are linked to atomic structure, octahedral p-orbital bonding, and vacancy distribution.
- The inter-correlation between vacancy distribution and bonding nature in PCMs requires further investigation.
Purpose of the Study:
- To investigate the effect of vacancy distribution on the octahedral p-orbital bonding network in Ge-Sb-Te PCMs.
- To establish a link between vacancy distribution and the physical properties of PCMs.
Main Methods:
- Utilized a simple tight-binding model for theoretical analysis.
- Employed ab initio calculations for detailed investigation.
- Rephrased vacancy disorders as a distribution of atomic chain pieces.
Main Results:
- The octahedral p-orbital bonding network in PCMs can be modeled as independent linear chains.
- Vacancy disorders were successfully rephrased as distributions of these atomic chain pieces.
- Established a connection between vacancy distribution and material properties.
Conclusions:
- Vacancy distribution significantly influences the octahedral p-orbital bonding network in PCMs.
- The proposed model provides a framework for understanding and predicting material properties based on vacancy distribution.
- This research offers insights into tailoring PCMs for specific applications through structural control.
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