Evidence for a quantum spin Hall phase in graphene decorated with Bi2Te3 nanoparticles
Abstract
Realization of the quantum-spin-Hall effect in graphene devices has remained an outstanding challenge dating back to the inception of the field of topological insulators. Graphene's exceptionally weak spin-orbit coupling -stemming from carbon's low mass- poses the primary obstacle. We experimentally and theoretically study artificially enhanced spin-orbit coupling in graphene via random decoration with dilute Bi2Te3 nanoparticles. Remarkably, multi-terminal resistance measurements suggest the presence of helical edge states characteristic of a quantum-spin-Hall phase; the magnetic-field and temperature dependence of the resistance peaks, X-ray photoelectron spectra, scanning tunneling spectroscopy, and first-principles calculations further support this scenario. These observations highlight a pathway to spintronics and quantum-information applications in graphene-based quantum-spin-Hall platforms.
- Publication:
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Science Advances
- Pub Date:
- November 2018
- DOI:
- 10.1126/sciadv.aau6915
- arXiv:
- arXiv:1806.07027
- Bibcode:
- 2018SciA....4.6915H
- Keywords:
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- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- doi:10.1126/sciadv.aau6915