Journal
MATERIALS
Volume 14, Issue 12, Pages -Publisher
MDPI
DOI: 10.3390/ma14123289
Keywords
atomic chain; Su-Schrieffer-Heeger model; density of states; van Hove singularities; localized states; hybrid systems
Categories
Funding
- National Science Centre, Poland [2018/31/B/ST3/02370]
Ask authors/readers for more resources
Investigating mid-gap 1D topological states and their electronic properties on different 2D hybrid structures reveals that these structures substantially influence topological states and induce strong asymmetry in their energy structures. Additionally, topological edge states can appear at different energies near the surface DOS edges.
Mid-gap 1D topological states and their electronic properties on different 2D hybrid structures are investigated using the tight binding Hamiltonian and the Green's function technique. There are considered straight armchair-edge and zig-zag Su-Schrieffer-Heeger (SSH) chains coupled with real 2D electrodes which density of states (DOS) are characterized by the van Hove singularities. In this work, it is shown that such 2D substrates substantially influence topological states end evoke strong asymmetry in their on-site energetic structures, as well as essential modifications of the spectral density function (local DOS) along the chain. In the presence of the surface singularities the SSH topological state is split, or it is strongly localized and becomes dispersionless (tends to the atomic limit). Additionally, in the vicinity of the surface DOS edges this state is asymmetrical and consists of a wide bulk part together with a sharp localized peak in its local DOS structure. Different zig-zag and armachair-edge configurations of the chain show the spatial asymmetry in the chain local DOS; thus, topological edge states at both chain ends can appear for different energies. These new effects cannot be observed for ideal wide band limit electrodes but they concern 1D topological states coupled with real 2D hybrid structures.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available