Thick Does the Trick: Genesis of Ferroelectricity in 2D GeTe-Rich (GeTe)m(Sb2Te3)n Lamellae

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Stefano Cecchi - , Università degli Studi di Milano Bicocca, Leibniz-Institut im Forschungsverbund Berlin e.V (Autor:in)
  • Jamo Momand - , University of Groningen (Autor:in)
  • Daniele Dragoni - , Università degli Studi di Milano Bicocca (Autor:in)
  • Omar Abou El Kheir - , Università degli Studi di Milano Bicocca (Autor:in)
  • Federico Fagiani - , Polytechnic University of Milan (Autor:in)
  • Dominik Kriegner - , Professur für Theoretische Festkörperphysik, Czech Academy of Sciences (Autor:in)
  • Christian Rinaldi - , Polytechnic University of Milan (Autor:in)
  • Fabrizio Arciprete - , University of Rome Tor Vergata (Autor:in)
  • Vaclav Holý - , Karlsuniversität Prag, Masaryk University (Autor:in)
  • Bart J. Kooi - , University of Groningen (Autor:in)
  • Marco Bernasconi - , Università degli Studi di Milano Bicocca (Autor:in)
  • Raffaella Calarco - , Leibniz-Institut im Forschungsverbund Berlin e.V, National Research Council of Italy (CNR) (Autor:in)

Abstract

The possibility to engineer (GeTe)m(Sb2Te3)n phase-change materials to co-host ferroelectricity is extremely attractive. The combination of these functionalities holds great technological impact, potentially enabling the design of novel multifunctional devices. Here an experimental and theoretical study of epitaxial (GeTe)m(Sb2Te3)n with GeTe-rich composition is presented. These layered films feature a tunable distribution of (GeTe)m(Sb2Te3)1 blocks of different sizes. Breakthrough evidence of ferroelectric displacement in thick (GeTe)m(Sb2Te3)1 lamellae is provided. The density functional theory calculations suggest the formation of a tilted (GeTe)m slab sandwiched in GeTe-rich blocks. That is, the net ferroelectric polarization is confined almost in-plane, representing an unprecedented case between 2D and bulk ferroelectric materials. The ferroelectric behavior is confirmed by piezoresponse force microscopy and electroresistive measurements. The resilience of the quasi van der Waals character of the films, regardless of their composition, is also demonstrated. Hence, the material developed hereby gathers in a unique 2D platform the phase-change and ferroelectric switching properties, paving the way for the conception of innovative device architectures.

Details

OriginalspracheEnglisch
Aufsatznummer2304785
FachzeitschriftAdvanced science
Jahrgang11
Ausgabenummer1
PublikationsstatusVeröffentlicht - 5 Jan. 2024
Peer-Review-StatusJa

Externe IDs

PubMed 37988708

Schlagworte

Schlagwörter

  • 2D ferroelectrics, density functional theory calculations, molecular beam epitaxy, phase-change materials, van der Waals