Definitive Surface Magnetotransport Study of SmB${}_6$

Abstract

After the theoretical prediction that SmB${}_6$ is a topological Kondo insulator, there has been an explosion of studies on the SmB${}_6$ surface. However, there is not yet an agreement on even the most basic quantities such as the surface carrier density and mobility. In this paper, we carefully revisit Corbino disk magnetotransport studies to find those surface transport parameters. We first show that subsurface cracks exist in the SmB${}_6$ crystals, arising both from surface preparation and during the crystal growth. We provide evidence that these hidden subsurface cracks are additional conduction channels, and the large disagreement between earlier surface SmB${}_6$ studies may originate from previous interpretations not taking this extra conduction path into account. We provide an update of a more reliable magnetotransport data than the previous one (Phys. Rev. B 92, 115110) and find that the orders-of-magnitude large disagreements in carrier density and mobility come from the surface preparation and the transport geometry rather than the intrinsic sample quality. From this magnetotransport study, we find an updated estimate of the carrier density and mobility of 2.71$\times$10${}^{13}$ (1/cm${}^2$) and 104.5 (cm${}^2$/V$\cdot$sec), respectively. We compare our results with other studies of the SmB${}_6$ surface. By this comparison, we provide insight into the disagreements and agreements of the previously reported angle-resolved photoemission spectroscopy, scanning tunneling microscopy, and magnetotorque quantum oscillations measurements.

References in corpus (41)

• Angle-resolved photoemission spectroscopy of the cuprate superconductors
• Topological Kondo Insulators
• Surface electronic structure of the topological Kondo insulator candidate correlated electron system SmB6
• Low-temperature surface conduction in the Kondo insulator SmB${}_6$
• Correlated Topological Insulators with Mixed Valence
• Quantum oscillations in Kondo Insulator SmB${}_6$
• Observation of in-gap surface states in the Kondo insulator SmB6 by photoemission
• Unconventional Fermi surface in an insulating state
• A theory of Topological Kondo Insulators
• Direct observation of the spin texture in strongly correlated SmB6 as evidence of the topological Kondo insulator
• Single particle relaxation time versus transport scattering time in a 2D graphene layer
• Surface and Bulk Electronic Structure of the Strongly Correlated System SmB${}_6$ and Implications for a Topological Kondo Insulator
• The quantum scattering time and its implications on scattering sources in graphene (Supplementary)
• The quantum scattering time and its implications on scattering sources in graphene
• Tuning bulk and surface conduction in topological Kondo insulator SmB6
• Fermi surface in the absence of a Fermi liquid in the Kondo insulator SmB${}_6$
• One-dimensional edge state transport in a topological Kondo insulator
• Samarium hexaboride: A trivial surface conductor
• Kondo hybridisation and the origin of metallic states at the (001) surface of SmB6
• Imaging emergent heavy Dirac fermions of a topological Kondo insulator
• Weak Antilocalization and Linear Magnetoresistance in The Surface State of SmB6
• Anomalous 3D bulk AC conduction within the Kondo gap of SmB${}_6$ single crystals
• Observation of perfect Andreev reflection due to Klein paradox in a topological superconducting state
• Quantum oscillations in flux-grown SmB6 with embedded aluminum
• Heavy surface state in a possible topological Kondo insulator: Magneto-thermoelectric transport on the (011)-plane of SmB${}_6$
• Robustness of the Insulating Bulk in the Topological Kondo Insulator SmB${}_6$
• 4$f$ crystal field ground state of the strongly correlated topological 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
• Magnetic and defect probes of the SmB${}_6$ surface state
• Consistency between ARPES and STM measurements on SmB${}_6$
• Non-trivial surface states of samarium hexaboride at the (111) surface
• Observation of a well-defined hybridization gap and in-gap states on the SmB6 (001) surface
• Observation of the superconducting proximity effect in the surface state of SmB6 thin films
• Bulk Rotational Symmetry Breaking in Kondo Insulator SmB6
• Electrical detection of surface spin polarization of candidate topological Kondo insulator SmB6
• Reduction of the low-temperature bulk gap in samarium hexaboride under high magnetic fields
• Consistency of Photoemission and Quantum Oscillations for Surface States of SmB6
• Influence of Helical Spin Structure on the Magnetoresistance of an Ideal Topological Insulator
• Ultrafast observation of electron hybridization and in-gap states formation in Kondo insulator SmB6

Cited by in corpus (7)

• Topological surface conduction in Kondo insulator YbB${}_{12}$
• Bulk transport paths through defects in floating zone and Al flux grown SmB${}_6$
• Extraordinary Bulk Insulating Behavior in the Strongly Correlated Materials FeSi and FeSb${}_2$
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Topological surface states in the Kondo insulator YbB${}_{12}$ revealed via planar tunneling spectroscopy
• Surface excitations relaxation in the Kondo insulator Sm${}_{1-x}$Gd${}_x$B${}_6$
• Observation of the superconducting proximity effect from surface states in SmB${}_6$/YB${}_6$ thin film heterostructures via terahertz spectroscopy