相关论文: Steps on current-voltage characteristics of a sili…
Considering a double-barrier structure formed by a silicon quantum dot covered by natural oxide, we derive simple conditions for the conductance of the dot to become a step-like function of the number of doping atoms inside the dot, with…
We report electron transport measurements of a silicon double dot formed in multi-gated metal-oxide-semiconductor structures with a 15-nm-thick silicon-on-insulator layer. Tunable tunnel coupling enables us to observe an excitation spectrum…
In this work, we have investigated conduction through an artificial molecule comprising two coupled quantum dots. The question addressed is the role of inter-dot coupling on electronic transport. We find that the current through the…
We compute the current voltage characteristic of a chain of identical Josephson circuits characterized by a large ratio of Josephson to charging energy that are envisioned as the implementation of topologically protected qubits. We show…
We calculate the current-voltage (I-V) characteristic of a Josephson junction containing a resonant level in the weakly coupled regime (resonance width small compared to the superconducting gap). The phase $\phi$ across the junction becomes…
The charge doped into a semiconductor in a field effect transistor (FET) is generally confined to the interface of the semiconductor. A planar step at the interface causes a potential drop due to the strong electric field of the FET, which…
The modern primary voltage standard is based on the AC Josephson effect and the ensuing Shapiro steps, where a microwave tone applied to a Josephson junction yields a constant voltage $hf/2e$ ($h$ is Planck's constant and $e$ the electron…
An exact solution is presented for tunneling through a negative-U d-fold degenerate molecular quantum dot weakly coupled to electrical leads. The tunnel current exhibits hysteresis if the level degeneracy of the negative-U dot is larger…
Percolation phenomena are investigated and discussed in three kinds of nanostructures: first two are nanocrystalline silicon-based systems, Si nanodots embedded in amorphous SiO2 matrix and porous silicon formed by an oxidized nanowire…
Effects of a coupling between the mechanical vibrations of a quantum dot placed between the two leads of a single electron transistor and coherent tunneling of electrons through a single level in the dot has been studied. We have found that…
The quantum Josephson voltage standard is well established across the metrology community for many years. It relies on the synchronisation of the flux tunneling in the S/I/S Josepson junctions (JJ) with the microwave radiation (MW). The…
The current-voltage characteristic of a driven superconducting Josephson junction displays discrete steps. This phenomenon, called the Shapiro steps, forms today's voltage standard! Here, we report the observation of Shapiro steps in a…
Superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson tunnel junctions based on Nb\Al2O3\Ni\Cu\Nb stacks with a thickness step in the metallic NiCu interlayer were fabricated. The step height of a few 0.1 nm was defined by…
We consider the transport spectroscopy of a quantum dot with an even number of electrons at finite bias voltage within the Coulomb blockade diamond. We calculate the tunneling current due to the elastic and inelastic co-tunneling processes…
Current-voltage characteristics were measured in the mixed state of Y1Ba2Cu3O(7-delta) superconducting films in the regime where flux flow becomes unstable and the differential conductivity dj/dE becomes negative. Under conditions where its…
We investigate dynamical transport aspects of a combined nanomechanical-superconducting device in which Cooper pair tunneling interfere with the mechanical motion of a vibrating molecular quantum dot embedded in a Josephson junction. Six…
The phase diagram of superconducting copper oxides is calculated as a function of doping based on a theory of dynamic stripe induced superconductivity. The two major conclusions from the theory and the numerical analysis are that T* (the…
Current-voltage measurements have been made at room temperature on a Si-rich silicon oxide film deposited via Electron-Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition (ECR-PECVD) and annealed at 750 - 1000$ ^\circ$C. The…
Detailed understanding of the role of single dopant atoms in host materials has been crucial for the continuing miniaturization in the semiconductor industry as local charging and trapping of electrons can completely change the behaviour of…
We observe a series of discontinuities in the above gap current/voltage characteristics of highly transmissive Nb/Si superconductor/semiconductor interfaces. The bias at which each switch occurs decreases in quantized steps as a function of…