Electrical resistance of individual defects at a topological insulator surface
نویسندگان
چکیده
Three-dimensional topological insulators host surface states with linear dispersion, which manifest as a Dirac cone. Nanoscale transport measurements provide direct access to the transport properties of the Dirac cone in real space and allow the detailed investigation of charge carrier scattering. Here we use scanning tunnelling potentiometry to analyse the resistance of different kinds of defects at the surface of a (Bi0.53Sb0.47)2Te3 topological insulator thin film. We find the largest localized voltage drop to be located at domain boundaries in the topological insulator film, with a resistivity about four times higher than that of a step edge. Furthermore, we resolve resistivity dipoles located around nanoscale voids in the sample surface. The influence of such defects on the resistance of the topological surface state is analysed by means of a resistor network model. The effect resulting from the voids is found to be small compared with the other defects.
منابع مشابه
The Department of Electrical Engineering
Materials with Dirac-type electronic band structure have recently drawn much interest. These materials revealed unique electrical, thermal and optical properties, which can be potentially used in future highspeed electronics. In this dissertation research, I investigate on two different classes of Dirac materials: graphene and topological insulators of the bismuth telluride (Bi2Te3) family. The...
متن کاملElectrical detection of spin-polarized surface states conduction in (Bi(0.53)Sb(0.47))2Te3 topological insulator.
Strong spin-orbit interaction and time-reversal symmetry in topological insulators enable the spin-momentum locking for the helical surface states. To date, however, there has been little report of direct electrical spin injection/detection in topological insulator. In this Letter, we report the electrical detection of spin-polarized surface states conduction using a Co/Al2O3 ferromagnetic tunn...
متن کاملMagnetism-induced massive Dirac spectra and topological defects in the surface state of Cr-doped Bi2Se3-bilayer topological insulators
1 Department of Physics, California Institute of Technology, Pasadena, CA 91125, USA 2 Institute of Quantum Matter and Information, California Institute of Technology, Pasadena, CA 91125, USA 3 Department of Electrical Engineering, University of California, Los Angeles, CA 90095, USA 4 Kavli Nanoscience Institute, California Institute of Technology, Pasadena, CA 91125, USA * E-mail: ncyeh@calte...
متن کاملImpact of Pollution Location on Time and Frequency Characteristics of Leakage Current of Porcelain Insulator String under Different Humidity and Contamination Severity
One of the important factors influencing outdoor insulators performance is pollution phenomenon. The pollution, especially during humidity condition, reduces superficial resistance of insulator and lead to a flow of Leakage Currents (LC) on the insulator surface, which may result in total flashover. The LC characteristics are affected by parameters such as nature and severity of pollution. Loca...
متن کاملThin films of topological Kondo insulator candidate SmB6: Strong spin-orbit torque without exclusive surface conduction
The advent of topological insulators (TIs), a novel class of materials that harbor a metallic spin-chiral surface state coexisting with band-insulating bulk, opens up new possibilities for spintronics. One promising route is current-induced switching of an adjacent magnetic layer via spin-orbit torque (SOT), arising from the large spin-orbit coupling intrinsically possessed by TIs. The Kondo in...
متن کامل