Persistent Optical Gating of a Topological Insulator

Abstract

Topological insulators (TIs) have attracted much attention due to their spin-polarized surface and edge states, whose origin in symmetry gives them intriguing quantum-mechanical properties. Robust control over the chemical potential of TI materials is important if these states are to become useful in new technologies, or as a venue for exotic physics. Unfortunately, chemical potential tuning is challenging in TIs in part because the fabrication of electrostatic top-gates tends to degrade material properties and the addition of chemical dopants or adsorbates can cause unwanted disorder. Here, we present an all-optical technique which allows persistent, bidirectional gating of a (Bi,Sb)2Te3 channel by optically manipulating the distribution of electric charge below its interface with an insulating SrTiO3 substrate. In this fashion we optically pattern p-n junctions in a TI material, which we subsequently image using scanning photocurrent microscopy. The ability to dynamically write and re-write mesoscopic electronic structures in a TI may aid in the investigation of the unique properties of the topological insulating phase. The optical gating effect may be adaptable to other material systems, providing a more general mechanism for reconfigurable electronics.

5 pages, 5 figures

References in corpus (11)

• Gate-Voltage Control of Chemical Potential and Weak Anti-localization in Bismuth Selenide
• Rapid Surface Oxidation as a Source of Surface Degradation Factor for Bi2Se3
• Weak Localization and Antilocalization in Topological Insulator Thin Films with Coherent Bulk-Surface Coupling
• Characterizing the Structure of Topological Insulator Thin Films
• Spin-based Mach-Zehnder interferometry in topological insulator p-n junctions
• Photoemission induced gating of topological insulator
• Chemical Potential Fluctuations in Topological Insulator (Bi${}_{0.5}$Sb${}_{0.5}$)${}_2$Te${}_3$ Films Visualized by Photocurrent Spectroscopy
• Electron and Hole Injection via Charge Transfer at the Topological-Insulator $B{i}_{2-x}S{b}_{x}T{e}_{3-y}S{e}_y$/Organic-Molecule Interface
• Topological Control: Systematic control of topological insulator Dirac fermion density on the surface of Bi2Te3
• Micro-metric electronic patterning of a topological band structure using a photon beam
• Unconventional band structure for a periodically gated surface of a three dimensional Topological Insulator

Cited by in corpus (13)

• Direct visualization of current induced spin accumulation in topological insulators
• Synergetic Behavior in 2D Layered Material/Complex Oxide Heterostructures
• Spin Hall photoconductance in a 3D topological insulator at room temperature
• Confinement and Fermion Doubling Problem in Dirac-like Hamiltonians
• Local optical control of ferromagnetism and chemical potential in a topological insulator
• Semiconductor channel mediated photodoping in h-BN encapsulated monolayer MoSe2 phototransistors
• Non-volatile rewritable frequency tuning of a nanoelectromechanical resonator using photoinduced doping
• Switchable quantized conductance in topological insulators revealed by the Shockley-Ramo theorem
• Unconventional band structure for a periodically gated surface of a three dimensional Topological Insulator
• Switching on surface conduction in a topological insulator
• Non-local Chemical Potential Modulation in Topological Insulators Via Electric Field Driven Trapped Charge Migration
• Terahertz Optics Driven Phase Transition in Two-Dimensional Multiferroics
• Chargeable photoconductivity in Van der Waals heterojunctions