Multiple topological interface states in silicene
Silicene is a 2D topological insulator due to its fairly large spin–orbital interaction and features a buckled lattice structure that allows one to control the effective mass of Dirac electrons by a perpendicular electric field. We propose the use of a spatially alternative electric field to generat...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2014-01-01
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| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/16/4/045015 |
| _version_ | 1797751418422034432 |
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| author | S K Wang J Wang K S Chan |
| author_facet | S K Wang J Wang K S Chan |
| author_sort | S K Wang |
| collection | DOAJ |
| description | Silicene is a 2D topological insulator due to its fairly large spin–orbital interaction and features a buckled lattice structure that allows one to control the effective mass of Dirac electrons by a perpendicular electric field. We propose the use of a spatially alternative electric field to generate multiple topologically-protected interface states (TIS) in the bulk silicene. It is shown that when the valley-dependent electron mass (defining the Chern number of an insulating bulk silicene) changes its sign or discontinues due to spatial variation of the electric field, multiple TIS appear in the insulating bulk silicene. The TIS come from the K and $K\prime $ valleys and sustain dissipationless valley or spin–valley-dependent currents, which are immune to both the valley-conservation and spin-observation scattering. It is also found that the coupling among TIS due to spatial electron tunneling excites the TIS, and whether there is an excitation gap or not depends on the even or odd TIS number. Our findings may shed light on manufacturing topological electron devices. |
| first_indexed | 2024-03-12T16:49:15Z |
| format | Article |
| id | doaj.art-10f35a0a23084eadb2330736e5de2c48 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:49:15Z |
| publishDate | 2014-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-10f35a0a23084eadb2330736e5de2c482023-08-08T11:25:11ZengIOP PublishingNew Journal of Physics1367-26302014-01-0116404501510.1088/1367-2630/16/4/045015Multiple topological interface states in siliceneS K Wang0J Wang1K S Chan2Department of Physics, Southeast University , Nanjing 210096, Peopleʼs Republic of ChinaDepartment of Physics, Southeast University , Nanjing 210096, Peopleʼs Republic of ChinaDepartment of Physics and Materials Science, City University of Hong Kong , Tat Chee Avenue, Kowloon, Hong Kong, Peopleʼs Republic of China; Shenzhen Research Institute, City University of Hong Kong , Shenzhen, Peopleʼs Republic of ChinaSilicene is a 2D topological insulator due to its fairly large spin–orbital interaction and features a buckled lattice structure that allows one to control the effective mass of Dirac electrons by a perpendicular electric field. We propose the use of a spatially alternative electric field to generate multiple topologically-protected interface states (TIS) in the bulk silicene. It is shown that when the valley-dependent electron mass (defining the Chern number of an insulating bulk silicene) changes its sign or discontinues due to spatial variation of the electric field, multiple TIS appear in the insulating bulk silicene. The TIS come from the K and $K\prime $ valleys and sustain dissipationless valley or spin–valley-dependent currents, which are immune to both the valley-conservation and spin-observation scattering. It is also found that the coupling among TIS due to spatial electron tunneling excites the TIS, and whether there is an excitation gap or not depends on the even or odd TIS number. Our findings may shed light on manufacturing topological electron devices.https://doi.org/10.1088/1367-2630/16/4/045015silicenetopological insulatorinterface stateelectric field85.75.-d73.43.-f |
| spellingShingle | S K Wang J Wang K S Chan Multiple topological interface states in silicene New Journal of Physics silicene topological insulator interface state electric field 85.75.-d 73.43.-f |
| title | Multiple topological interface states in silicene |
| title_full | Multiple topological interface states in silicene |
| title_fullStr | Multiple topological interface states in silicene |
| title_full_unstemmed | Multiple topological interface states in silicene |
| title_short | Multiple topological interface states in silicene |
| title_sort | multiple topological interface states in silicene |
| topic | silicene topological insulator interface state electric field 85.75.-d 73.43.-f |
| url | https://doi.org/10.1088/1367-2630/16/4/045015 |
| work_keys_str_mv | AT skwang multipletopologicalinterfacestatesinsilicene AT jwang multipletopologicalinterfacestatesinsilicene AT kschan multipletopologicalinterfacestatesinsilicene |