Nanowires made of chalcogenide alloys are of interest for use in phase-change nonvolatile memories. For this application, insights into the thermal properties of such nanowires and, in particular, into the crystallization kinetics at the atomic level are crucial. Toward this end, we have performed large-scale atomistic simulations of ultrathin nanowires (9 nm in diameter) of the prototypical phase-change compound GeTe. We made use of an interatomic potential generated by the neural network fitting of a large ab initio database to compute the thermal properties of the nanowires. By melting a portion of a nanowire, we investigated the velocity of recrystallization as a function of temperature. The simulations show that the melting temperature of the nanowire is about 100 K below the melting temperature of the bulk, which yields a reduction by about a factor of 2 of the maximum crystallization speed. Further, analysis of the structural properties of the amorphous phase of the nanowire suggests a possible origin of the reduction of the resistance drift observed experimentally in nanowires with respect to the bulk.

Gabardi, S., Baldi, E., Bosoni, E., Campi, D., Caravati, S., Sosso, G., et al. (2017). Atomistic Simulations of the Crystallization and Aging of GeTe Nanowires. JOURNAL OF PHYSICAL CHEMISTRY. C, 121(42), 23827-23838 [10.1021/acs.jpcc.7b09862].

Atomistic Simulations of the Crystallization and Aging of GeTe Nanowires

Gabardi, S.;Campi, D.;Caravati, S.;Sosso, G. C.;Bernasconi, M.
2017

Abstract

Nanowires made of chalcogenide alloys are of interest for use in phase-change nonvolatile memories. For this application, insights into the thermal properties of such nanowires and, in particular, into the crystallization kinetics at the atomic level are crucial. Toward this end, we have performed large-scale atomistic simulations of ultrathin nanowires (9 nm in diameter) of the prototypical phase-change compound GeTe. We made use of an interatomic potential generated by the neural network fitting of a large ab initio database to compute the thermal properties of the nanowires. By melting a portion of a nanowire, we investigated the velocity of recrystallization as a function of temperature. The simulations show that the melting temperature of the nanowire is about 100 K below the melting temperature of the bulk, which yields a reduction by about a factor of 2 of the maximum crystallization speed. Further, analysis of the structural properties of the amorphous phase of the nanowire suggests a possible origin of the reduction of the resistance drift observed experimentally in nanowires with respect to the bulk.
Articolo in rivista - Articolo scientifico
nanowires; phase change materials; molecular dynamics simulations; non-volatile memories;
English
2017
121
42
23827
23838
partially_open
Gabardi, S., Baldi, E., Bosoni, E., Campi, D., Caravati, S., Sosso, G., et al. (2017). Atomistic Simulations of the Crystallization and Aging of GeTe Nanowires. JOURNAL OF PHYSICAL CHEMISTRY. C, 121(42), 23827-23838 [10.1021/acs.jpcc.7b09862].
File in questo prodotto:
File Dimensione Formato  
Gabardi-2017-J Phys Chem-VoR.pdf

Solo gestori archivio

Descrizione: Article
Tipologia di allegato: Publisher’s Version (Version of Record, VoR)
Dimensione 9.77 MB
Formato Adobe PDF
9.77 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Gabardi-2017-J Phys Chem-AAM.pdf

accesso aperto

Descrizione: Article
Tipologia di allegato: Author’s Accepted Manuscript, AAM (Post-print)
Dimensione 9.14 MB
Formato Adobe PDF
9.14 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/176623
Citazioni
  • Scopus 41
  • ???jsp.display-item.citation.isi??? 37
Social impact