Signature of Large-Gap Quantum Spin Hall State in the Layered Mineral Jacutingaite
| Autor: | György Baranka, Zsolt Endre Horváth, Anna Vymazalová, Áron Pekker, Ákos Hoffmann, Péter Nemes-Incze, János Koltai, Péter Vancsó, Gergő Kukucska, Levente Tapasztó, Konrád Kandrai, Katalin Kamarás |
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| Rok vydání: | 2020 |
| Předmět: |
Letter
Band gap Low-dimensional materials FOS: Physical sciences Bioengineering 02 engineering and technology law.invention law Mesoscale and Nanoscale Physics (cond-mat.mes-hall) General Materials Science Quantum spin Hall effect (QSH) Spin (physics) Quantum Quantum computer Topological insulator Physics Condensed Matter - Materials Science Condensed Matter - Mesoscale and Nanoscale Physics Condensed matter physics Mechanical Engineering Materials Science (cond-mat.mtrl-sci) Heterojunction General Chemistry Scanning tunneling microscopy (STM) 021001 nanoscience & nanotechnology Condensed Matter Physics Charge carrier Scanning tunneling microscope 0210 nano-technology |
| Zdroj: | Nano Letters |
| ISSN: | 1530-6992 1530-6984 |
| Popis: | Quantum spin Hall (QSH) insulators are materials that feature an insulating bulk and host edge states protected by time-reversal symmetry. The helical locking of spin and momentum in these states suppresses backscattering of charge carriers, promising applications from low-power electronics to quantum computing. A major challenge for applications is the identification of large gap QSH materials, which would enable room temperature dissipationless transport in their edge states. Here we show that the layered mineral jacutingaite (Pt$_2$HgSe$_3$) is a candidate QSH material, realizing the long sought after the Kane-Mele insulator. Using scanning tunneling microscopy, we measure a band gap of 110 meV, above room temperature, and identify the hallmark edge states. By calculating the $\mathbb{Z}_2$ invariant, we confirm the topological nature of the gap. Being a layered mineral, it is stable in air and can be thinned down to a few atomic layers by mechanical exfoliation. Furthermore, we demonstrate that it can be integrated into heterostructures with other two-dimensional materials. This adds a topological insulator to the 2D quantum material library, greatly expanding the possibilities for tuning 2D electron systems using stacks of layered materials. |
| Databáze: | OpenAIRE |
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