Related papers: Gate tunable non-linear currents in bilayer graphe…
Graphene's linear dispersion relation and the attendant implications for bipolar electronics applications have motivated a range of experimental efforts aimed at producing p-n junctions in graphene. Here we report electrical transport…
We have developed a process to fabricate suspended graphene devices with local bottom gates, and tested it by realizing electrostatically controlled pn junctions on a suspended graphene mono-layer nearly 2 micrometers long. Measurements as…
Graphene is a promising candidate for optoelectronic applications. In this report, a double gated bilayer graphene FET has been made using a combination of electrostatic and electrolytic gating in order to form an abrupt p-n junction. The…
We study ballistic transport in periodically gated bilayer graphene as a candidate for a 2D electronic metamaterial. Our calculations use the equilibrium Green function formalism and take into account quantum corrections to charge density…
Twisted two-dimensional structures open new possibilities in band structure engineering. At magic twist angles, flat bands emerge, which give a new drive to the field of strongly correlated physics. In twisted double bilayer graphene dual…
One of the unique features of graphene is that the Fermi wavelength of its charge carriers can be tuned electrostatically over a wide range. This allows in principle to tune the transparency of a pn-junction electrostatically, as this…
With its electrically tunable light absorption and ultrafast photoresponse, graphene is a promising candidate for high-speed chip-integrated photonics. The generation mechanisms of photosignals in graphene photodetectors have been studied…
If a device like a graphene nanoribbon (GNR) has all its four corners attached to electric current leads, the device becomes a quantum junction through which two electrical circuits can interact. We study such system theoretically for…
We have fabricated a device which includes two lateral p-n junctions on an n-type GaAs/Al$_{0.33}$Ga$_{0.67}$As heterostructure. A section of the n-type material has been converted to p-type by removing dopants and applying a voltage to a…
The potential of graphene-based materials consisting of one or a few layers of graphite for integrated electronics originates from the large room-temperature carrier mobility in these systems (approx. 10,000 cm2/Vs). However, the…
We report low-temperature measurements of two adjacent, gate-defined Josephson junctions (JJs) in magic-angle twisted bilayer graphene (MATBG) at a moir\'e filling factor near $\nu = -2$. We show that both junctions exhibit a prominent,…
We fabricated graphene pnp devices, by embedding pre-defined local gates in an oxidized surface layer of a silicon substrate. With neither dielectric-material deposition nor electron-beam irradiation on the graphene, we obtained…
We report on transport properties of monolayer graphene with a laterally modulated potential profile, employing striped top gate electrodes with spacings of 100 nm to 200 nm. Tuning of top and back gate voltages gives rise to local charge…
We study spin transport in normal/ferromagnetic/normal graphene junctions where a gate electrode is attached to the ferromagnetic graphene. We find that due to the exchange field of the ferromagnetic graphene, spin current through the…
The problem of electrostatic screening of a charged line by undoped or weakly doped graphene is treated beyond the linear-response theory. The induced electron density is found to be approximately doping independent, n(x)~(log x)^2/x^2, at…
We present a highly controllable double quantum dot device based on bilayer graphene. Using a device architecture of interdigitated gate fingers, we can control the interdot tunnel coupling between 1 to 4 GHz and the mutual capacitive…
Recent work investigated graphene's hydrogenation with independent control of the electric field, E, and charge density, n, in the crystal and showed that the process is controlled by n. Here, we demonstrate layer-selective…
We theoretically calculate the charge-supercurrent through a ballistic graphene junction where superconductivity is induced via the proximity-effect. Both monolayer and bilayer graphene are considered, including the possibility of strain in…
We explore the device potential of tunable-gap bilayer graphene FET exploiting the possibility of opening a bandgap in bilayer graphene by applying a vertical electric field via independent gate operation. We evaluate device behavior using…
The concept of a novel graphene P-I-N junction switching device with a nanoribbon is proposed, and its basic operation is demonstrated in an experiment. The concept aims to optimize the operation scheme for graphene transistors toward a…