Two-Dimensional Topological Insulator State in Cadmium Arsenide Thin Films
| العنوان: | Two-Dimensional Topological Insulator State in Cadmium Arsenide Thin Films |
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| المؤلفون: | Alexander C. Lygo, Binghao Guo, Arman Rashidi, Victor Huang, Pablo Cuadros-Romero, Susanne Stemmer |
| المصدر: | Physical Review Letters. 130 |
| بيانات النشر: | American Physical Society (APS), 2023. |
| سنة النشر: | 2023 |
| مصطلحات موضوعية: | Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy |
| الوصف: | Two-dimensional topological insulators (2D TIs) are a highly desired quantum phase but few materials have demonstrated clear signatures of a 2D TI state. It has been predicted that 2D TIs can be created from thin films of three-dimensional TIs by reducing the film thickness until the surface states hybridize. Here, we employ this technique to report the first observation of a 2D TI state in epitaxial thin films of cadmium arsenide, a prototype Dirac semimetal in bulk form and a 3D TI in thin films. Using magnetotransport measurements with electrostatic gating, we observe a Landau level spectrum and quantum Hall effect that are in excellent agreement with those of an ideal 2D TI. Specifically, we observe a crossing of the zeroth Landau levels at a critical magnetic field. We show that the film thickness can be used to tune the critical magnetic field. Moreover, a larger change in film thickness causes a transition from a 2D TI to a 2D trivial insulator, just as predicted by theory. The high degree of tunability available in epitaxial cadmium arsenide heterostructures can thus be used to fine-tune the 2D TI, which is essential for future topological devices. Accepted for publication in Physical Review Letters. Fixed issues with the display of Fig. 3 in the pdf in this version |
| تدمد: | 1079-7114 0031-9007 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d5bcfe75ee42733c25343c00fef1a3c0 https://doi.org/10.1103/physrevlett.130.046201 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....d5bcfe75ee42733c25343c00fef1a3c0 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10797114 00319007 |
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