Phase change memory has been developed into a mature technology capable of storing information in a fast and non-volatile way1,2,3, with potential for neuromorphic computing applications4,5,6. However, its future impact in electronics depends crucially on how the materials at the core of this technology adapt to the requirements arising from continued scaling towards higher device densities. A common strategy to fine-tune the properties of phase change memory materials, reaching reasonable thermal stability in optical data storage, relies on mixing precise amounts of different dopants, resulting often in quaternary or even more complicated compounds6,7,8. Here we show how the simplest material imaginable, a single element (in this case, antimony), can become a valid alternative when confined in extremely small volumes. This compositional simplification eliminates problems related to unwanted deviations from the optimized stoichiometry in the switching volume, which become increasingly pressing when devices are aggressively miniaturized9,10. Removing compositional optimization issues may allow one to capitalize on nanosize effects in information storage.
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The research leading to these results has received funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013/ under REA grant agreement no. 610781, from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement nos 640003 and 682675), and from Deutsche Forschungsgemeinschaft (DFG) through the collaborative research centre Nanoswitches (SFB 917). We also acknowledge the computational resources provided by JARA-HPC from RWTH Aachen University under projects nos JARA0150 and JARA0176. Finally, we thank E. Eleftheriou and Wabe W. Koelmans at IBM Research Zurich for their support of this work.
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Salinga, M., Kersting, B., Ronneberger, I. et al. Monatomic phase change memory. Nature Mater 17, 681–685 (2018). https://doi.org/10.1038/s41563-018-0110-9
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