Large twisting angles in bilayer graphene moiré quantum dot structures

Bucko, Jozef; Herman, František

doi:10.1103/physrevb.103.075116

Cited by 13 publications

(5 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, introducing a finite twist between the two layers is a natural extension of this work which offers further degrees of tunability, both in the spatial fluctuation of mass terms due to different stackings and the different confined or edge states in the dot regions. 102,103…”

Section: Discussionmentioning

confidence: 99%

Valley current generation using biased bilayer graphene dots

Solomon,

Power

2021

Preprint

View full text Add to dashboard Cite

Intrinsic and extrinsic valley Hall effects are predicted to emerge in graphene systems with uniform or spatially-varying mass terms. Extrinsic mechanisms, mediated by the valley-dependent scattering of electrons at the Fermi surface, can be directly linked to quantum transport simulations. This is a promising route towards more complete experimental investigation of valleytronic phenomena in graphene, but a major obstacle is the difficulty in applying the sublattice-dependent potentials required. Here we show that strongly valley-dependent scattering also emerges from bilayer graphene quantum dots, where the gap size can be easily modulated using the interlayer potentials in dualgated devices. Robust valley-dependent scattering and concomitant valley currents are observed for a range of systems, and we investigate the role of dot size, mass strength and additional potential terms. Finally, we note that a strong valley splitting of electronic current also emerges when a biased bilayer dot is embedded in a single layer of graphene, but that the effect is less robust than for a bilayer host. Our findings suggest that bilayer graphene devices with custom mass profiles provide an excellent platform for future valleytronic exploration of two-dimensional materials.

show abstract

Section: Discussionmentioning

confidence: 99%

Valley current generation using biased bilayer graphene dots

Solomon,

Power

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Atomically thin nanomaterials provide an exciting platform for quantum technologies [1][2][3][4]. Bilayer graphene has specifically drawn great attention [5][6][7][8][9] and it was shown that bilayer graphene is a promising host for gatedefined quantum dots [10]. Quantum dots are one of the prime candidates for scalable and highly controllable quantum devices [11][12][13][14].…”

Section: Introductionmentioning

confidence: 99%

Automated Reconstruction of Bound States in Bilayer Graphene Quantum Dots

et al. 2023

Self Cite

View full text Add to dashboard Cite

Bilayer graphene is a nanomaterial that allows for well-defined, separated quantum states to be defined by electrostatic gating and, therefore, provides an attractive platform to construct tunable quantum dots. When a magnetic field perpendicular to the graphene layers is applied, the graphene valley degeneracy is lifted, and splitting of the energy levels of the dot is observed. Although bilayer graphene quantum dots have recently been realized in experiments, it is critically important to devise robust methods that can identify the observed quantum states from accessible measurement data. Here, we develop an efficient algorithm for extracting the model parameters needed to characterize the states of a bilayer graphene quantum dot. Specifically, we put forward a Hamiltonian-guided random search method and demonstrate robust identification of quantum states on both simulated and experimental data.

show abstract

“…Polarization-dependent selection rules have been extended to TBG QDs, offering a comprehensive atlas of optical conductivity spectra and providing insights into size-scaling behavior dominated by the twist angle, enabling the manipulation of optical properties for integrated carbon optoelectronics [8]. Additionally, large-angle twisting in single-layer graphene has been investigated, emphasizing the potential of adjusting position symmetry in graphene systems [9]. Finally, the dominance of interlayer polarizability and charge transfer at small twist angles in TBG sheds light on interlayer coupling and charge transfer potential in graphene-based nanomaterials [10].…”

Section: Introductionmentioning

confidence: 99%

Single electron transistor based on twisted bilayer graphene quantum dots

Huang,

He,

Cao

et al. 2023

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Electrical properties of twisted bilayer graphene exhibit angle-dependent characteristics, sparking a thriving development in the field of twistronics. However, the application of quantum dots (QDs) made of twisted bilayer graphene in single-electron transistors (SETs) remains largely unexplored so far. We here investigate the electronic properties of twisted bilayer graphene QDs (TBG QDs) within a SET configuration. We compare the performance of conventional and double-gated SET structures and find that the double-gated configuration provides enhanced control over the electronic properties of TBG QDs. We analyze the influence of rotation angles on the charge stability diagrams and observe that the linear and quadratic gate-island coupling strengths generally decrease as the rotation angle decreases. Furthermore, we quantify the effect of QD size on the charge stability diagrams and find that the size of the diamond-shaped regions decreases as the TBG QD size increases. Results presented herein may help pave the way for realization and application of TBG QDs based SET.

show abstract

Large twisting angles in bilayer graphene moiré quantum dot structures

Cited by 13 publications

References 26 publications

Valley current generation using biased bilayer graphene dots

Valley current generation using biased bilayer graphene dots

Automated Reconstruction of Bound States in Bilayer Graphene Quantum Dots

Single electron transistor based on twisted bilayer graphene quantum dots

Contact Info

Product

Resources

About