2014/11/30 by Yu Pan, Y. Pan, D. Wu +17 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Charge-carrier density #Condensed matter physics #Doping #Electrical resistivity and conductivity #Graphene research and applications #Physics #Quantum mechanics #Surface (topology) #Surface states #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1088/1367-2630/16/12/123035
published as New J. Phys. 16, 123035(2014) · 16 pages, 6 figures, accepted for publication in New Journal of Physics
openalex publication_date 2014/12/15 · arxiv created 2015/05/07 · arxiv updated 2015/05/08 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In 3D topological insulators achieving a genuine bulk-insulating state is an important research topic. Recently, the material system (Bi,Sb) 2 (Te,Se) 3 (BSTS) has been proposed as a topological insulator with high resistivity and a low carrier concentration (Ren et al 2011 Phys. Rev. B 84 165311 ). Here we present a study to further refine the bulk-insulating properties of BSTS. We have synthesized BSTS single crystals with compositions around x = 0.5 and y = 1.3. Resistance and Hall effect measurements show high resistivity and record low bulk carrier density for the composition Bi Sb Te Se . The analysis of the resistance measured for crystals with different thicknesses within a parallel resistor model shows that the surface contribution to the electrical transport amounts to 97% when the sample thickness is reduced to 1 μ m. The magnetoconductance of exfoliated BSTS nanoflakes shows 2D weak antilocalization with as expected for transport dominated by topological surface states.