Disorder effects of vacancies on the electronic transport properties of realistic topological insulator nanoribbons: The case of bismuthene

Author(s)

Pezo, Armando ^{[1, 2]} ; Focassio, Bruno ^{[1, 2]} ; Schleder, Gabriel R. ^{[1, 2]} ; Costa, Marcio ^{[1, 3]} ; Lewenkopf, Caio ^[3] ; Fazzio, Adalberto ^{[1, 2]}

Affiliation

^[1] CNPEM, Brazilian Nanotechnol Natl Lab LNNano, BR-13083970 Campinas, SP - Brazil

^[2] Fed Univ ABC UFABC, Ctr Nat Sci & Humanities, BR-09210580 Santo Andre, SP - Brazil

^[3] Univ Fed Fluminense, Inst Fis, BR-24210346 Niteroi, RJ - Brazil

• Document type: Journal article
• Source: PHYSICAL REVIEW MATERIALS; v. 5, n. 1 JAN 19 2021.
• Web of Science Citations: 0

Abstract

The robustness of topological materials against disorder and defects is presumed but has not been demon-strated explicitly in realistic systems. In this work, we use state-of-the-art density functional theory and recursive nonequilibrium Green's functions methods to study the effect of disorder on the electronic transport of long nanoribbons, up to 157 nm, as a function of vacancy concentration. In narrow nanoribbons, a finite-size effect gives rise to hybridization between the edge states erasing topological protection. Hence, even small vacancy concentrations enable backscattering events. We show that the topological protection is more robust for wide nanoribbons, but surprisingly it breaks down at moderate structural disorder. Our study helps to establish some bounds on defective bismuthene nanoribbons as promising candidates for spintronic applications. (AU)

• FAPESP's process: 17/02317-2 - Interfaces in materials: electronic, magnetic, structural and transport properties
• Grantee: Adalberto Fazzio
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/04527-0 - Interface between crystalline topological insulators and 2D-trivial materials: defect proximity study
• Grantee: Bruno Focassio
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 17/18139-6 - Machine learning for Materials Science: 2D materials discovery and design
• Grantee: Gabriel Ravanhani Schleder
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 16/14011-2 - Electronic properties: interfaces between topological insulators (TI-TI)
• Grantee: Marcio Jorge Teles da Costa
• Support Opportunities: Scholarships in Brazil - Post-Doctoral