# Low-temperature surface conduction in the Kondo insulator SmB6

@article{Wolgast2013LowtemperatureSC, title={Low-temperature surface conduction in the Kondo insulator SmB6}, author={Steven Wolgast and Çağlıyan Kurdak and Kai Sun and J. W. Allen and Dae-Jeong Kim and Zachary Fisk}, journal={Physical Review B}, year={2013}, volume={88}, pages={180405} }

We study the transport properties of the Kondo insulator SmB6 with a specialized configuration designed to distinguish bulk-dominated conduction from surface-dominated conduction. We find that as the material is cooled below 4 K, it exhibits a crossover from bulk to surface conduction with a fully insulating bulk. We take the robustness and magnitude of the surface conductivity, as is manifest in the literature of SmB6, to be strong evidence for the topological insulator metallic surface states…

## 246 Citations

### Surface Hall Effect and Nonlocal Transport in SmB6: Evidence for Surface Conduction

- PhysicsScientific reports
- 2013

These results serve as proof that at low temperatures SmB6 has a metallic surface that surrounds an insulating bulk, paving the way for transport studies of the surface state in this proposed TKI material.

### Kondo insulator SmB6 under strain: surface dominated conduction near room temperature

- Physics
- 2016

SmB6 is a strongly correlated mixed-valence Kondo insulator with a newly discovered surface state, proposed to be of non-trivial topological origin. However, the surface state dominates electrical…

### Surface-dominated conduction up to 240 K in the Kondo insulator SmB6 under strain.

- PhysicsNature materials
- 2017

With 0.7% tensile strain, surface-dominated conduction is reported in SmB6 at up to a temperature of 240 K, persisting even after the strain has been removed, and it is noted that this amount of strain can be induced in epitaxial SmB 6 films via substrate in potential device applications.

### Surface Hall Effect and Nonlocal Transport in SmB 6 : Evidence for Surface

- Physics
- 2013

A topological insulator (TI) is an unusual quantum state in which the insulating bulk is topologically distinct from vacuum, resulting in a unique metallic surface that is robust against…

### Screened moments in a Kondo insulator

- Physics
- 2017

Long known to have thermodynamic properties at odds with its insulating electrical transport, SmB6 has been the subject of great debate as it is unclear whether its unusual properties are related to…

### Topological aspect of Kondo insulator

- Physics
- 2016

The experimental observations of the in-gap state by various measurements on a Kondo insulator provide a special and interesting character on the insulator. We show that the system is classified into…

### Robust coherence phenomena and surface states in magnetically alloyed SmB6

- Physics
- 2019

Samarium hexaboride is a candidate for the topological Kondo insulator state, in which Kondo coherence is predicted to give rise to an insulating gap spanned by topological surface states. Here we…

### Correlation between Bulk Thermodynamic Measurements and the Low-Temperature-Resistance Plateau in SmB 6

- Physics
- 2014

Topological insulators are materials characterized by dissipationless, spin-polarized surface states resulting from non-trivial band topologies. Recent theoretical models and experiments suggest that…

### Topological surface conduction in Kondo insulator YbB12

- PhysicsJournal of Physics D: Applied Physics
- 2021

Kondo insulators have recently aroused great interest because they are promising materials that host a topological insulator state caused by the strong electron interactions. Moreover, recent…

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