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Peierls distortion mediated reversible phase transition in GeTe under pressure.

ABSTRACT: With the advent of big synchrotron facilities around the world, pressure is now routinely placed to design a new material or manipulate the properties of materials. In GeTe, an important phase-change material that utilizes the property contrast between the crystalline and amorphous states for data storage, we observed a reversible phase transition of rhombohedral ? rocksalt ? orthorhombic ? monoclinic coupled with a semiconductor ? metal interconversion under pressure on the basis of ab initio molecular dynamics simulations. This interesting reversible phase transition under pressure is believed to be mediated by Peierls distortion in GeTe. Our results suggest a unique way to understand the reversible phase transition and hence the resistance switching that is crucial to the applications of phase-change materials in nonvolatile memory. The present finding can also be expanded to other IV-VI semiconductors.

SUBMITTER: Sun Z

PROVIDER: S-EPMC3341046 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Peierls distortion mediated reversible phase transition in GeTe under pressure.

Sun Zhimei Z Zhou Jian J Mao Ho-Kwang HK Ahuja Rajeev R

Proceedings of the National Academy of Sciences of the United States of America 20120402 16

With the advent of big synchrotron facilities around the world, pressure is now routinely placed to design a new material or manipulate the properties of materials. In GeTe, an important phase-change material that utilizes the property contrast between the crystalline and amorphous states for data storage, we observed a reversible phase transition of rhombohedral ↔ rocksalt ↔ orthorhombic ↔ monoclinic coupled with a semiconductor ↔ metal interconversion under pressure on the basis of ab initio m ...[more]

PMID: 22474349

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