Observation of Anderson localization in ultrathin films of three-dimensional topological insulators

Abstract

Anderson localization, the absence of diffusive transport in disordered systems, has been manifested as hopping transport in numerous electronic systems, whereas in recently discovered topological insulators it has not been directly observed. Here we report experimental demonstration of transition from diffusive transport in the weak antilocalization regime to variable range hopping transport in the Anderson localization regime with ultrathin (Bi${}_{1-x}$Sb${}_x$)${}_2$Te${}_3$ films. As disorder becomes stronger, negative magnetoconductivity due to the weak antilocalization is gradually suppressed, and eventually positive magnetoconductivity emerges when the electron system becomes strongly localized. This works reveals the critical role of disorder in the quantum transport properties of ultrathin topological insulator films, in which theories have predicted rich physics related to topological phase transitions.

6 pages, 4 figures, to appear in PRL, supplemental material available upon request

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Cited by in corpus (13)

• Enhanced electron dephasing in three-dimensional topological insulators
• Disorder Effects in Topological States -- Brief Review of the Recent Developments
• Observation of multichannel quantum coherent transport and electron-electron interaction in Bi2Te3 single crystal
• Disorder-driven topological phase transition in Bi2Se3 films
• Spin-dependent scattering induced negative magnetoresistance in topological insulator Bi2Te3 nanowires
• Magnetic-field-induced topological phase transition in Fe-doped (Bi,Sb)${}_2$Se${}_3$ heterostructures
• Topological Phase Transitions Induced by Disorder in Magnetically Doped (Bi, Sb)${}_2$Te${}_3$ Thin Films
• Reversible and nonvolatile manipulation of the spin-orbit interaction in ferroelectric field-effect transistors based on a two-dimensional bismuth oxychalcogenide
• Identifying the fingerprints of topological states by tuning magnetoresistance in a semimetal: the case of topological half-Heusler Pt1-xAuxLuSb
• Accessing topological surface states and negative MR in sculpted nanowires of Bi2Te3 at ultra-low temperature
• Probing Electron Localization and Delocalization in the Selective Long-Range Tight-Binding Model
• Correlated disorder induced anomalous transport in magnetically doped topological insulators
• Robust topological insulator surface state in MBE grown (Bi_{1-x}Sb_x)_2Se_3