Topologically Nontrivial Phase-Change Compound GeSb2Te4


Nurmamat M., Okamoto K., Zhu S., Menshchikova T. V., Rusinov I. P., Korostelev V. O., ...More

ACS Nano, vol.14, no.7, pp.9059-9065, 2020 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 14 Issue: 7
  • Publication Date: 2020
  • Doi Number: 10.1021/acsnano.0c04145
  • Journal Name: ACS Nano
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Biotechnology Research Abstracts, Chemical Abstracts Core, Chimica, Compendex, EMBASE, INSPEC, MEDLINE
  • Page Numbers: pp.9059-9065
  • Keywords: Inertia-free Dirac currents, Linearly dispersive bulk band, Phase-change materials, Pump-probe method, Topologically nontrivial phase
  • Open Archive Collection: Article
  • Azerbaijan State University of Economics (UNEC) Affiliated: Yes

Abstract

Chalcogenide phase-change materials show strikingly contrasting optical and electrical properties, which has led to their extensive implementation in various memory devices. By performing spin-, time-, and angle-resolved photoemission spectroscopy combined with the first-principles calculation, we report the experimental results that the crystalline phase of GeSb2Te4 is topologically nontrivial in the vicinity of the Dirac semimetal phase. The resulting linearly dispersive bulk Dirac-like bands that cross the Fermi level and are thus responsible for conductivity in the stable crystalline phase of GeSb2Te4 can be viewed as a 3D analogue of graphene. Our finding provides us with the possibility of realizing inertia-free Dirac currents in phase-change materials.