Topological insulating behaviour in conducting property of crystalline Ge-Sb-Te

Abstract

We report a discovery, through first-principles calculations, that crystalline Ge-Sb-Te (GST) phase-change materials exhibit the topological insulating property. Our calculations show that the materials become topological insulator or develop conducting surface-like interface states depending on the layer stacking sequence. It is shown that the conducting interface states originate from topological insulating Sb2Te3 layers in GSTs and can be crucial to the electronic property of the compounds. These interface states are found to be quite resilient to atomic disorders but sensitive to the uniaxial strains. We presented the mechanisms that destroy the topological insulating order in GSTs and investigated the role of Ge migration that is believed to be responsible for the amorphorization of GSTs.

13 pages, 4 figures

References in corpus (3)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry

Cited by in corpus (3)

• Weak antilocalization and disorder-enhanced electron interactions in crystalline GeSbTe
• Strain tuning of topological band order in cubic semiconductors
• Three-dimensional topological insulators: A review on host materials