Magnetotransport in nanocrystalline SmB6 thin films
SmB6 has been predicted to be a prototype of topological Kondo insulator (TKI) but its direct experimental evidence as a TKI is still lacking to date. Here we report on our search for the signature of a topological surface state and investigation of the effect of disorder on transport properties in...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
AIP Publishing LLC
2015-07-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/1.4927398 |
| _version_ | 1819157117807886336 |
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| author | Jie Yong Yeping Jiang Xiaohang Zhang Jongmoon Shin Ichiro Takeuchi Richard L. Greene |
| author_facet | Jie Yong Yeping Jiang Xiaohang Zhang Jongmoon Shin Ichiro Takeuchi Richard L. Greene |
| author_sort | Jie Yong |
| collection | DOAJ |
| description | SmB6 has been predicted to be a prototype of topological Kondo insulator (TKI) but its direct experimental evidence as a TKI is still lacking to date. Here we report on our search for the signature of a topological surface state and investigation of the effect of disorder on transport properties in nanocrystalline SmB6 thin films through longitudinal magnetoresistance and Hall coefficient measurements. The magnetoresistance (MR) at 2 K is positive and linear (LPMR) at low field and become negative and quadratic at higher field. While the negative part is understood from the reduction of the hybridization gap due to Zeeman splitting, the positive dependence is similar to what is observed in other topological insulators (TI). We conclude that the LPMR is a characteristic of TI and is related to the linear dispersion near the Dirac cone. The Hall resistance shows a sign change around 50K. It peaks and becomes nonlinear around 10 K then decreases below 10 K. This indicates that carriers with opposite signs emerge below 50 K. These properties indicate that the surface states are robust and probably topological in our nanocrystalline films. |
| first_indexed | 2024-12-22T16:03:40Z |
| format | Article |
| id | doaj.art-461c845abf624ea0956bc709c8f5ebf6 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-12-22T16:03:40Z |
| publishDate | 2015-07-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-461c845abf624ea0956bc709c8f5ebf62022-12-21T18:20:38ZengAIP Publishing LLCAIP Advances2158-32262015-07-0157077144077144-710.1063/1.4927398045507ADVMagnetotransport in nanocrystalline SmB6 thin filmsJie Yong0Yeping Jiang1Xiaohang Zhang2Jongmoon Shin3Ichiro Takeuchi4Richard L. Greene5Center for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USACenter for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USACenter for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USADepartment of Materials Science & Engineering, University of Maryland, College Park, Maryland 20742, USACenter for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USACenter for Nanophysics & Advanced Materials, University of Maryland, College Park, Maryland 20742, USASmB6 has been predicted to be a prototype of topological Kondo insulator (TKI) but its direct experimental evidence as a TKI is still lacking to date. Here we report on our search for the signature of a topological surface state and investigation of the effect of disorder on transport properties in nanocrystalline SmB6 thin films through longitudinal magnetoresistance and Hall coefficient measurements. The magnetoresistance (MR) at 2 K is positive and linear (LPMR) at low field and become negative and quadratic at higher field. While the negative part is understood from the reduction of the hybridization gap due to Zeeman splitting, the positive dependence is similar to what is observed in other topological insulators (TI). We conclude that the LPMR is a characteristic of TI and is related to the linear dispersion near the Dirac cone. The Hall resistance shows a sign change around 50K. It peaks and becomes nonlinear around 10 K then decreases below 10 K. This indicates that carriers with opposite signs emerge below 50 K. These properties indicate that the surface states are robust and probably topological in our nanocrystalline films.http://dx.doi.org/10.1063/1.4927398 |
| spellingShingle | Jie Yong Yeping Jiang Xiaohang Zhang Jongmoon Shin Ichiro Takeuchi Richard L. Greene Magnetotransport in nanocrystalline SmB6 thin films AIP Advances |
| title | Magnetotransport in nanocrystalline SmB6 thin films |
| title_full | Magnetotransport in nanocrystalline SmB6 thin films |
| title_fullStr | Magnetotransport in nanocrystalline SmB6 thin films |
| title_full_unstemmed | Magnetotransport in nanocrystalline SmB6 thin films |
| title_short | Magnetotransport in nanocrystalline SmB6 thin films |
| title_sort | magnetotransport in nanocrystalline smb6 thin films |
| url | http://dx.doi.org/10.1063/1.4927398 |
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