Magnetic-field-induced charge redistribution in disordered graphene double quantum dots." Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. We have studied the trans...

We report tunneling spectroscopy experiments on a bilayer graphene double quantum dot device that can be tuned by all-graphene lateral gates. The diameter of the two quantum dots are around 50 nm and the constrictions acting as tunneling barriers are 30 nm in width. The double quantum dot features additional energies on the order of 20 meV. Charge stability diagrams allow us to study the tunabl...

Graphene double quantum dots (DQDs) open to use charge or spin degrees of freedom for storing and manipulating quantum information in this new electronic material. However, impurities and edge disorders in etched graphene nano-structures hinder the ability to control the inter-dot tunnel coupling, tC, the most important property of the artificial molecule. Here we report measurements of tC in a...

Quantum interference causes a wavefunction to have sensitive spatial dependence, and this has a significant effect on quantum transport. For example, in a quantum-dot system, the conductance can depend on the lead positions. We investigate, for graphene quantum dots, the conductance variations with the lead positions. Since for graphene the types of boundaries, e.g., zigzag and armchair, can f...

We study electronic transport in quantum-dot structures made of graphene. Focusing on the rectangular dot geometry and utilizing the non-equilibrium Green's function to calculate the transmission in the tight-binding framework, we find significant fluctuations in the transmission as a function of the electron energy. The fluctuations are correlated with the formation of quantum scarring states,...

Single-layer core-shell structures consisting of graphene as the core and hexagonal boron nitride as the shell are studied using the first-principles plane-wave method within density functional theory. Electronic energy level structure is analyzed as a function of the size of both core and shell. It is found that the confinement of electrons in a two-dimensional graphene quantum dot is reduced ...

Following a brief review of the device-friendly features of graphene, recent work on its Green's functions with and without a normal magnetic field are discussed, for an infinite graphene sheet and also for a quantum dot, with analyses of the Landau-quantized energy spectra of the sheet and dot. The random phase approximation dielectric response of graphene is reviewed and discussed in connecti...

The aim of this work was to design and control, using genetic algorithm (GA) for parameter optimization, one-charge-qubit quantum logic gates σx, σy, and σz, using two bound states as a qubit space, of circular graphene quantum dots in a homogeneous magnetic field. The method employed for the proposed gate implementation is through the quantum dynamic control of the qubit subspace with an oscil...

We study an interaction of 2D quasiparticles with linear dispersion E = ±u|p| (graphene) with impurity potentials. It is shown that in 1D potential well (quantum wire) there are discrete levels, corresponding to localized states, whereas in 2D well (quantum dot) there are no such states. Scattering cross-section of electrons (holes) of graphene by an axially symmetric potential well is found an...

We study an interaction of 2D quasiparticles with linear dispersion E = ±u|p| (graphene) with impurity potential. It is shown that in 1D potential well (quantum wire) there are discrete levels, corresponding to localized states, whereas in 2D well (quantum dot) there are no such states. It is found the scattering cross-section of electrons (holes) of graphene on the axially symmetric potential ...