Unraveling Quantum Hall Breakdown in Bilayer Graphene with Scanning Gate Microscopy

Connolly, M. R.; Puddy, R; Logoteta, Demetrio; Marconcini, Paolo; Roy, Mervyn; Griffiths, J. P.; Jones, G. A. C.; Maksym, P. A.; Macucci, Massimo; Smith, Charles G.

doi:10.1021/nl3015395

Cited by 44 publications

(34 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the zigzag rib-bon, in the transverse direction they adopted the discretization by Susskind [39] and in the longitudinal direction the discretization by Stacey; for the armchair ribbon they used the Stacey discretization in both directions. Snyman et al [40] previously adopted the alternative method of mapping the Dirac equation onto a Chalker-Coddington network model [41], which in the past was used to describe percolation in disordered samples in the quantum Hall effect [42][43][44].…”

Section: Introductionmentioning

confidence: 99%

High-performance solution of the transport problem in a graphene armchair structure with a generic potential

et al. 2014

View full text Add to dashboard Cite

We propose an efficient numerical method to study the transport properties of armchair graphene ribbons in the presence of a generic external potential. The method is based on a continuum envelope-function description with physical boundary conditions. The envelope functions are computed in the reciprocal space, and the transmission is then obtained with a recursive scattering matrix approach. This allows a significant reduction of the computational time with respect to finite difference simulations.

show abstract

Section: Introductionmentioning

confidence: 99%

High-performance solution of the transport problem in a graphene armchair structure with a generic potential

et al. 2014

View full text Add to dashboard Cite

show abstract

“…SGM has been also used to study 2D materials . As an example, SGM revealed electron‐doped and hole‐doped mesoscopic domains in graphene‐based FETs (namely GFET) .…”

Section: Single‐probe Advanced Characterization Methodsmentioning

confidence: 99%

“…In particular, the local electrical transport through graphene was manipulated as a function of the position of the tip and potential applied, and the measurements indicate that the large spatial fluctuation of carriers density in the graphene sheet was related to extrinsic doping, most probably from metal contacts, graphene edges, structural defects and polymer residues . When applied to the study of bilayer graphene, SGM revealed paths of electrons during the breakdown of the quantum Hall effect . Apart from that, SGM has been also used to explore Wigner and Kondo physics in QPCs, and the interference and Coulomb blockade in QPC and quantum spots/rings .…”

Section: Single‐probe Advanced Characterization Methodsmentioning

confidence: 99%

Emerging Scanning Probe–Based Setups for Advanced Nanoelectronic Research

Hui

Wen

Chen

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

Figure 3. a) Schematic of the CAFM integrated into the SEM. b) SEM image of a CAFM tip landed on the NW arrays. c) Top-view SEM image of the ZnO NW arrays. d) AFM topographic map of the as-fabricated ZnO NW arrays collected in tapping mode using a Si tip. Reproduced with permission. [109] Despite the main drawback of this method is the instability of the filament due to the extreme thinness of the lamella, one work proved a stable cyclic operation (more than 60 switching cycles) in 30 nm CuTe-based conductive bridging random access memory (CBRAM). [119] Multiprobe Advanced Characterization MethodsDespite the high lateral resolution of SPM represents a very strong advantage compared to traditional electrical characterization methods (i.e., probe station), the use of only one probe Adv. Funct. Mater. 2020, 30, 1902776Figure 4. a) TEM image of an overview of a sample; each finger contains a stack of Ni/HfO 2 /SiO x /n + Si. Current-time plots indicate the typical b) SET and c) RESET processes. d) TEM image (top) and corresponding EDS nickel map (bottom) of the device in a SET state. Reproduced with permission. [114] Copyright 2015, Wiley VCH. e) I-V graph of in situ electroforming and RESET of Pt/ZnO/Pt where the top electrode (TE) was negatively biased while the bottom electrode (BE) was grounded, and corresponding f-h) electroforming and i,j) RESET images extracted. Reproduced with permission. [118]

show abstract

“…Figure 3(c) and 3(d) show the obtained main peak around R = 0 with the small satellite peaks. The averaged radius (r) of the bright spot and averaged spacing (D) between the spots were estimated from the peak width at half maximum of the main peak and the separation between satellite peak (Fig.3(c) and (d)), respectively defined by 2r and 2D − 4r [10,11]. The estimated values are r = 441 nm and D = 2.77 µm for the high-mobility sample and r = 386 nm and D = 1.97 µm for the low-mobility sample.…”

Section: Pacs Numbers: Valid Pacs Appear Herementioning

confidence: 99%

Real space imaging of the quantum-Hall incompressible states influenced by the strong disorder

Wang

Hashimoto

Hirayama

2019

2019 Compound Semiconductor Week (CSW)

View full text Add to dashboard Cite

While the disorder-induced quantum Hall (QH) effect has been studied previously, the effect of disorder potential on microscopic features of the integer QH effect remains unclear, particularly for the incompressible (IC) strip. In this research, a scanning gate microscope incorporated with the non-equilibrium transport technique is used to study the influence of potential disorder on the QH IC strip emerging near the sample edge. It was found that different mobility samples with different disorder potentials showed the same spatial dependence of the IC strip on the filling factor, while in the low-mobility sample alone, strong pattern modulations such as bright and dark spots appeared in the IC strip. This pattern is related to the stronger potential disorder inherent to the low-mobility sample. It could be concluded that this disorder strongly affects the QH state, and the applied technique can be effectively used to detect the IC strip in a low-mobility sample. PACS numbers: Valid PACS appear hereUnder a strong magnetic field, two-dimensional electron gas (2DEG) forms quantum Hall (QH) phases, such as insulating incompressible (IC) and metallic compressible (C) phases. The microscopic configuration of these phases, determined by both the nonlinear screening effect and electrostatic potential landscape in the 2DEG plane, plays an essential role for the QH effect. When the filling factor (ν) is close to the integer ν, the IC region covering the interior of the 2DEG protects the counter propagating C edge channels from backscattering in between the channels [1]. The bulk IC phase emerges owing to potential disorder at ν, deviating slightly from the exact integer ν, inducing the quantized Hall conductance that is widely persistent around an integer ν. This disorder-induced QH effect has been microscopically confirmed through scanning probe measurement [2, 3] that showed compressible paddles interspersed with the IC bulk phase, namely, localized states. On the other hand, the IC along the edge of the 2DEG governed by edge confinement potential [4] and its robust ν-dependence have recently been microscopically demonstrated for the high mobility Hall bar device by our nonequilibrium-transport assisted scanning gate imaging [5].While the disorder stabilizes integer QH effect, further strong disorder may significantly disturb the QH state. The localized states in the integer QH effect may be delocalized owing to disorder scattering [6]. When the disorder strength is sufficiently high, QH plateaus begin to collapse and finally cease the existence of the integer QH effect [6]. However, it is not clear how disorder potential disturbs microscopic features of the integer QH effect, particularly for the IC strip and its movement. In this study, we address influence of potential disorder on the IC strips in GaAs quantum wells with the different mobility samples. To the end, a non-equilibrium transport assisted scanning probe technique, which was previous (b) (c) (a) ΔV xx (μV) ν = 1.07 48 -30 0.02 0.00 2 μm ν = 1.07 25 -23 0.0...

show abstract

Unraveling Quantum Hall Breakdown in Bilayer Graphene with Scanning Gate Microscopy

Cited by 44 publications

References 59 publications

High-performance solution of the transport problem in a graphene armchair structure with a generic potential

High-performance solution of the transport problem in a graphene armchair structure with a generic potential

Emerging Scanning Probe–Based Setups for Advanced Nanoelectronic Research

Real space imaging of the quantum-Hall incompressible states influenced by the strong disorder

Contact Info

Product

Resources

About