Aging mechanisms in amorphous phase-change materials

[en] Aging is a ubiquitous phenomenon in glasses. In the case of phase-change materials, it leads to a drift in the electrical resistance, which hinders the development of ultrahigh density storage devices. Here we elucidate the aging process in amorphous GeTe, a prototypical phase-change material, by advanced numerical simulations, photothermal deflection spectroscopy and impedance spectroscopy experiments. We show that aging is accompanied by a progressive change of the local chemical order towards the crystalline one. Yet, the glass evolves towards a covalent amorphous network with increasing Peierls distortion, whose structural and electronic properties drift away from those of the resonantly bonded crystal. This behaviour sets phase-change materials apart from conventional glass-forming systems, which display the same local structure and bonding in both phases

Disciplines :

Physics

Author, co-author :

Raty, Jean-Yves ; Université de Liège > Département de physique > Physique expérimentale des matériaux nanostructurés

Zhang, wei

Luckas, Jennifer

Chen, Chao

Mazzarello, Riccardo

Bichara, Christophe

Wuttig, Matthias

Language :

English

Title :

Aging mechanisms in amorphous phase-change materials

Publication date :

24 June 2015

Journal title :

Nature Communications

eISSN :

2041-1723

Publisher :

Nature Pub.lishing Group, London, United Kingdom

Volume :

Issue :

7467

Pages :

1-8

Peer reviewed :

Peer Reviewed verified by ORBi

Tags :

CÉCI : Consortium des Équipements de Calcul Intensif
Tier-1 supercomputer

Additional URL :

http://dx.doi.org/10.1038/ncomms8467

Funders :

F.R.S.-FNRS - Fonds de la Recherche Scientifique [BE]
DGTRE - Région wallonne. Direction générale des Technologies, de la Recherche et de l'Énergie [BE]
Tier-1; Region Wallonne (grant 1117545)
ARC themotherm
RWTH Aachen JARA0089
ANR 11 BS08-0012
CÉCI - Consortium des Équipements de Calcul Intensif [BE]

Available on ORBi :

since 29 June 2015

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207

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149

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