TY  - JOUR
AU  - Möller, Sören
AU  - Banszerus, L.
AU  - Knothe, A.
AU  - Valerius, L.
AU  - Hecker, K.
AU  - Icking, E.
AU  - Watanabe, K.
AU  - Taniguchi, T.
AU  - Volk, Christian
AU  - Stampfer, C.
TI  - Impact of competing energy scales on the shell-filling sequence in elliptic bilayer graphene quantum dots
JO  - Physical review / B
VL  - 108
IS  - 12
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2024-03012
SP  - 125128
PY  - 2023
AB  - We report on a detailed investigation of the shell-filling sequence in electrostatically defined elliptic bilayer graphene quantum dots (QDs) in the regime of low charge carrier occupation, N≤12, by means of magnetotransport spectroscopy and numerical calculations. We show the necessity of including both short-range electron-electron interaction and wave-function-dependent valley g-factors for understanding the overall fourfold shell-filling sequence. These factors lead to an additional energy splitting at half filling of each orbital state and different energy shifts in out-of-plane magnetic fields. Analysis of 31 different bilayer graphene (BLG) QDs reveals that both valley g-factor and electron-electron interaction-induced energy splitting increase with decreasing QD size, validating theory. However, we find that the electrostatic charging energy of such gate-defined QDs does not correlate consistently with their size, indicating complex electrostatics. These findings offer significant insights for future BLG QD devices and circuit designs.
LB  - PUB:(DE-HGF)16
DO  - DOI:10.1103/PhysRevB.108.125128
UR  - https://juser.fz-juelich.de/record/1025623
ER  -