High-temperature quantum valley Hall effect with quantized resistance and a topological switch.
Science
; 385(6709): 657-661, 2024 Aug 09.
Article
in En
| MEDLINE
| ID: mdl-39024378
ABSTRACT
Edge states of a topological insulator can be used to explore fundamental science emerging at the interface of low dimensionality and topology. Achieving a robust conductance quantization, however, has proven challenging for helical edge states. In this work, we show wide resistance plateaus in kink states-a manifestation of the quantum valley Hall effect in Bernal bilayer graphene-quantized to the predicted value at zero magnetic field. The plateau resistance has a very weak temperature dependence up to 50 kelvin and is flat within a dc bias window of tens of millivolts. We demonstrate the electrical operation of a topology-controlled switch with an on/off ratio of 200. These results demonstrate the robustness and tunability of the kink states and its promise in constructing electron quantum optics devices.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Science
Year:
2024
Document type:
Article
Affiliation country:
United States