Topologically induced semiconductivity in icosahedral Al-Pd-Re and its approximants surface

Author(s)
Marian Krajci, Juergen Hafner
Abstract

We demonstrate that the opening of a semiconducting band-gap in the electronic spectrum of the i-Al-Pd-Re quasicrystal and its approximants is due to the formation of a topological band-gap, in analogy to the band-gap found in the FeSi (B20) structure. In both systems we have identified a network of linear chains of alternating Si(Al) and transition-metal (TM) atoms extending along twofold symmetry directions. In i-Al-Pd-Re the chains of alternating Al and TM atoms extend from a center of the pseudo-Mackay (M) cluster over the surface of the Bergman cluster to the center of another neighboring M cluster. Substitutional Al Pd defects and a fragmentation of the chains by phason defects lead to the formation of localized states in the band-gap. The band-gap of the real i-Al-Pd-Re quasicrystal is filled by localized states. The i-Al-Pd-Re quasicrystal thus behaves as a disordered semiconductor. © 2007 The American Physical Society. Society.

Organisation(s)
Computational Materials Physics
External organisation(s)
Slovenian Academy of Sciences and Arts (SASA)
Journal
Physical Review B
Volume
75
No. of pages
18
ISSN
1098-0121
DOI
https://doi.org/10.1103/PhysRevB.75.024116
Publication date
2007
Peer reviewed
Yes
Austrian Fields of Science 2012
1030 Physics, Astronomy
Portal url
https://ucris.univie.ac.at/portal/en/publications/topologically-induced-semiconductivity-in-icosahedral-alpdre-and-its-approximants-surface(37592993-bbbb-4248-aae4-5d138a7f1eee).html