Topologically non-trivial valley states in bilayer graphene quantum point contactsCitation formats
Standard
Topologically non-trivial valley states in bilayer graphene quantum point contacts. / Overweg, Hiske; Knothe, Angelika; Fabian, Thomas ; Linhart, L.; Rickhaus, Peter; Wernli, Lucien ; Watanabe, Kenji; Taniguchi, Takashi; Sanchez, David; Burgdörfer, Joachim; Libisch, Florian; Fal'ko, Vladimir; Ensslin, Klaus; Ihn, Thomas.
In: Physical Review Letters, Vol. 121, No. 25, 257702, 20.12.2018.Research output: Contribution to journal › Article › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Topologically non-trivial valley states in bilayer graphene quantum point contacts
AU - Overweg, Hiske
AU - Knothe, Angelika
AU - Fabian, Thomas
AU - Linhart, L.
AU - Rickhaus, Peter
AU - Wernli,, Lucien
AU - Watanabe, Kenji
AU - Taniguchi, Takashi
AU - Sanchez, David
AU - Burgdörfer, Joachim
AU - Libisch, Florian
AU - Fal'ko, Vladimir
AU - Ensslin, Klaus
AU - Ihn, Thomas
PY - 2018/12/20
Y1 - 2018/12/20
N2 - We present measurements of quantized conductance in electrostatically induced quantum point contacts in bilayer graphene. The application of a perpendicular magnetic field leads to an intricate pattern of lifted and restored degeneracies with increasing field: at zero magnetic field the degeneracy of quantized one-dimensional subbands is four, because of a twofold spin and a twofold valley degeneracy. By switching on the magnetic field, the valley degeneracy is lifted. Because of the Berry curvature, states from different valleys split linearly in magnetic field. In the quantum Hall regime fourfold degenerate conductance plateaus reemerge. During the adiabatic transition to the quantum Hall regime, levels from one valley shift by two in quantum number with respect to the other valley, forming an interweaving pattern that can be reproduced by numerical calculations.
AB - We present measurements of quantized conductance in electrostatically induced quantum point contacts in bilayer graphene. The application of a perpendicular magnetic field leads to an intricate pattern of lifted and restored degeneracies with increasing field: at zero magnetic field the degeneracy of quantized one-dimensional subbands is four, because of a twofold spin and a twofold valley degeneracy. By switching on the magnetic field, the valley degeneracy is lifted. Because of the Berry curvature, states from different valleys split linearly in magnetic field. In the quantum Hall regime fourfold degenerate conductance plateaus reemerge. During the adiabatic transition to the quantum Hall regime, levels from one valley shift by two in quantum number with respect to the other valley, forming an interweaving pattern that can be reproduced by numerical calculations.
U2 - 10.1103/physrevlett.121.257702
DO - 10.1103/physrevlett.121.257702
M3 - Article
VL - 121
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 25
M1 - 257702
ER -