Conductance fluctuations in disordered 2D topological insulator wires: From quantum spin-hall to ordinary phases

Hsu, H.C. ; Kleftogiannis, I. ; Guo, G.Y. ; Gopar, V.A. (Universidad de Zaragoza)

Resumen: Impurities and defects are ubiquitous in topological insulators (TIs) and thus understanding the effects of disorder on electronic transport is important. We calculate the distribution of the random conductance fluctuations P(G) of disordered 2D TI wires modeled by the Bernevig-Hughes-Zhang (BHZ) Hamiltonian with realistic parameters. As we show, the disorder drives the TIs into different regimes: metal (M), quantum spin-Hall insulator (QSHI), and ordinary insulator (OI). By varying the disorder strength and Fermi energy, we calculate analytically and numerically P(G) across the entire phase diagram. The conductance fluctuations follow the statistics of the unitary universality class ß = 2. At strong disorder and high energy, however, the size of the fluctuations dG reaches the universal value of the orthogonal symmetry class (ß = 1). At the QSHI-M and QSHI-OI crossovers, the interplay between edge and bulk states plays a key role in the statistical properties of the conductance.

Idioma: Inglés

DOI: 10.7566/JPSJ.87.034701

Año: 2018

Publicado en: JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 87, 3 (2018), 034701 [6 pp]
ISSN: 0031-9015

Factor impacto JCR: 1.57 (2018)

Categ. JCR: PHYSICS, MULTIDISCIPLINARY rank: 42 / 81 = 0.519 (2018) - Q3 - T2

Factor impacto SCIMAGO: 0.588 - Physics and Astronomy (miscellaneous) (Q2)

Financiación: info:eu-repo/grantAgreement/ES/MCIU/Subprograma Estatal de Movilidad 2013–2016-PRX16-00166
Financiación: info:eu-repo/grantAgreement/ES/MINECO/FIS2015-65078-C2-2-P

Tipo y forma: Article (PostPrint)

Área (Departamento): Área Física Teórica (Dpto. Física Teórica)