Abstract
Phase-change materials are some of the most promising materials for data-storage applications. They are already used in rewriteable optical data storage and offer great potential as an emerging non-volatile electronic memory. This review looks at the unique property combination that characterizes phase-change materials. The crystalline state often shows an octahedral-like atomic arrangement, frequently accompanied by pronounced lattice distortions and huge vacancy concentrations. This can be attributed to the chemical bonding in phase-change alloys, which is promoted by p-orbitals. From this insight, phase-change alloys with desired properties can be designed. This is demonstrated for the optical properties of phase-change alloys, in particular the contrast between the amorphous and crystalline states. The origin of the fast crystallization kinetics is also discussed.
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Acknowledgements
We thank J. Kalb and M. Salinga for critical reading of the manuscript and the European project WIND for financial support.
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Wuttig, M., Yamada, N. Phase-change materials for rewriteable data storage. Nature Mater 6, 824â832 (2007). https://doi.org/10.1038/nmat2009
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DOI: https://doi.org/10.1038/nmat2009
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