Tuning bulk and surface conduction in topological Kondo insulator SmB6

Abstract

Bulk and surface state contributions to the electrical resistance of single-crystal samples of the topological Kondo insulator compound SmB6 are investigated as a function of crystal thickness and surface charge density, the latter tuned by ionic liquid gating with electrodes patterned in a Corbino disk geometry on a single surface. By separately tuning bulk and surface conduction channels, we show conclusive evidence for a model with an insulating bulk and metallic surface states, with a crossover temperature that depends solely on the relative contributions of each conduction channel. The surface conductance, on the order of 100 e^2/h and electron-like, exhibits a field-effect mobility of 133 cm^2/V/s and a large carrier density of ~2x10^{14}/cm^2, in good agreement with recent photoemission results. With the ability to gate-modulate surface conduction by more than 25%, this approach provides promise for both fundamental and applied studies of gate-tuned devices structured on bulk crystal samples.

arXiv comment5 pages, 3 figures

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Cited by in corpus (68)

• Colloquium: Topological Band Theory
• Quantum Materials for Spin and Charge Conversion
• One-dimensional edge state transport in a topological Kondo insulator
• Möbius Kondo Insulators
• Imaging emergent heavy Dirac fermions of a topological Kondo insulator
• Observation of perfect Andreev reflection due to Klein paradox in a topological superconducting state
• Topological surface states interacting with bulk excitations in the Kondo insulator SmB${}_6$ revealed via planar tunneling spectroscopy
• Robustness of the Insulating Bulk in the Topological Kondo Insulator SmB${}_6$
• Magnetotransport Measurements of the Surface States of Samarium Hexaboride using Corbino Structures
• Hysteretic Magnetotransport in SmB6 at Low Magnetic Fields
• Spin Injection and Inverse Edelstein Effect in the Surface States of Topological Kondo Insulator SmB6
• Breakdown of the Kondo insulating state in SmB6 by introducing Sm vacancies
• Pressure-resistant intermediate valence in Kondo insulator SmB6
• Bulk Fermi surface of charge-neutral excitations in SmB6 or not: a heat-transport study
• Pressure-induced quantum phase transitions in topological insulator YbB6
• Consistency between ARPES and STM measurements on SmB${}_6$
• Properties of the donor impurity band in mixed valence insulators
• Field-dependent heat transport in the Kondo insulator SmB6 : phonons scattered by magnetic impurities
• Observation of the superconducting proximity effect in the surface state of SmB6 thin films
• Incomplete Protection of the Surface Weyl Cones of the Kondo Insulator SmB${}_6$: Spin Exciton Scattering
• A highly asymmetric nodal semimetal in bulk SmB6
• Excitonic and Nematic Instabilities on the Surface of Topological Kondo Insulators
• Surface-state-dominated transport in crystals of the topological crystalline insulator In-doped Pb${}_{1-x}$Sn${}_x$Te
• Comparative study of rare earth hexaborides using high resolution angle-resolved photoemission
• Chemical and valence reconstruction at the surface of SmB6 revealed with resonant soft x-ray reflectometry
• Metallic surface states in a correlated d-electron topological Kondo insulator candidate FeSb2
• Topological surface conduction in Kondo insulator YbB${}_{12}$
• Definitive Surface Magnetotransport Study of SmB${}_6$
• Resistivity saturation in Kondo insulators
• Surface-induced positive planar Hall effect in topological Kondo insulator SmB6 microribbons
• The Effects of Spin-Excitons on the Surface States of SmB6: A Photoemission Study
• Bulk Rotational Symmetry Breaking in Kondo Insulator SmB6
• Spin- and angle-resolved photoemission on the topological Kondo Insulator candidate: SmB6
• Robust Surface States indicated by Magnetotransport in SmB6 Thin Films
• Radio Frequency Tunable Oscillator Device Based on SmB6 Microcrystal
• Intrinsic Low-Temperature Magnetism in SmB6
• Electrical detection of surface spin polarization of candidate topological Kondo insulator SmB6
• Planar tunneling spectroscopy of the topological Kondo insulator SmB${}_6$
• Topological Kondo semimetal and insulator in AB-stacked heterobilayer transition metal dichalcogenides
• Quantum spin fluctuations in the bulk insulating state of pure and Fe-doped SmB6
• Reduction of the low-temperature bulk gap in samarium hexaboride under high magnetic fields
• Signature of surface state coupling in thin films of the topological Kondo insulator SmB${}_6$ from anisotropic magnetoresistance
• Ferromagnetism and glassiness on the surface of topological insulators
• Fragility of the Kondo insulating gap against disorder: relevance to recent puzzles in topological Kondo insulators
• Magnetic and electrical anisotropy with correlation and orbital effects in dimerized honeycomb ruthenate Li${}_2$RuO${}_3$
• Extraordinary Bulk Insulating Behavior in the Strongly Correlated Materials FeSi and FeSb${}_2$
• Coulomb drag in topological insulator films
• Electrical properties of SmB${}_6$ thin films prepared by pulsed laser deposition from a stoichiometric SmB${}_6$ target
• From bad metal to Kondo insulator: temperature evolution of the optical properties of SmB${}_6$
• Many-body breakdown of indirect gap in topological Kondo insulators
• Probing the interplay between surface and bulk states in the topological Kondo insulator SmB${}_6$ through conductance fluctuation spectroscopy
• Coulomb drag in topological materials
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Electrical detection of the inverse Edelstein effect on the surface of SmB${}_6$
• Low temperature resistivity studies of SmB6: Observation of twodimensional variable-range hopping conductivity
• Microwave Meissner Screening of Proximity coupled Topological Insulator / Superconductor Bilayers
• Topological surface states in the Kondo insulator YbB${}_{12}$ revealed via planar tunneling spectroscopy
• Hall coefficient diagnostics of surface state in pressurized SmB6
• Phase stability in SmB${}_6$
• Surface excitations relaxation in the Kondo insulator Sm${}_{1-x}$Gd${}_x$B${}_6$
• Persistence of correlation-driven surface states in SmB6 under pressure
• Surface Conductivity in Antiferromagnetic Semiconductor CrSb${}_2$
• Observation of the superconducting proximity effect from surface states in SmB${}_6$/YB${}_6$ thin film heterostructures via terahertz spectroscopy
• Nanoscale Conducting and Insulating Domains on YbB${}_6$
• SmB6: A material with anomalous energy distribution function of charge carriers?
• Intrinsic one-dimensional conducting channels in the Kondo insulator SmB6
• Electronic correlations and topology in Kondo insulator PuB${}_6$
• Effect of valence fluctuations on the ground state properties of SmB6