Related papers: Quantized Charge Pumping through a Carbon Nanotube…
Charge qubits formed in double quantum dots represent quintessential two-level systems that enjoy both ease of control and efficient readout. Unfortunately, charge noise can cause rapid decoherence, with typical single-qubit gate fidelities…
We investigate the field emission properties of nitrogenated and boronated carbon nanotubes using time-dependent density functional theory, were the wave function propagation is performed using the Crank-Nicholson algorithm. We extract the…
We have incorporated an aluminum single electron transistor directly into the defining gate structure of a semiconductor quantum dot, permitting precise measurement of the charge in the dot. Voltage biasing a gate draws charge from a…
We propose a method to dynamically generate and control the flow of spin-entangled electrons, each belonging to a spin-singlet, by means of adiabatic quantum pumping. The pumping cycle functions by periodic time variation of localized…
We investigate a recently developed scheme for quantized charge pumping based on single-parameter modulation. The device was realized in an AlGaAl-GaAs gated nanowire. It has been shown theoretically that non-adiabaticity is fundamentally…
We report a theoretical analysis of parametric electron pump through a quantum dot in the Kondo regime. In the adiabatic regime, we have derived the expression for pumped current in the Kondo regime using non-equilibrium Green's function.…
We have measured the electrical properties of individual bundles, or "ropes" of single-walled carbon nanotubes. Below ~10 K, the low bias conductance is suppressed for voltages below a few millivolts. In addition, dramatic peaks are…
We performed studies of coherent electronic transport through a single walled carbon nanotube. In the calculations multiple scattering on the contacts and interference processes were taken into account. Conductance is a composition of…
We report a method to derive the potential barrier profile shape in a dynamic quantum dot and show the loading statistics, and hence accuracy of electron transfer, depend significantly on the shape of the barrier. This method takes a…
Current can be pumped through a closed system by changing parameters (or fields) in time. Linear response theory (the Kubo formula) allows to analyze both the charge transport and the associated dissipation effect. We make a distinction…
Cavity optomechanics allows the characterization of a vibration mode, its cooling and quantum manipulation using electromagnetic fields. Regarding nanomechanical as well as electronic properties, single wall carbon nanotubes are a…
We report on electrical transport measurements in a carbon nanotube quantum dot coupled to a normal and a superconducting lead. Depending on the ratio of Kondo temperature $T_{K}$ and superconducting gap $\Delta$ the zero bias conductance…
We report on high-accuracy measurements of quantized current, sourced by a tunable-barrier single-electron pump at frequencies $f$ up to $1$ GHz. The measurements were performed with a new picoammeter instrument, traceable to the Josephson…
A battery is a work storage device, i.e. a device that stores energy in the form of work for later use by other devices. In this work, we study the realization of a quantum battery in a double quantum dot in series, charged by two…
In double quantum dot singlet-triplet qubits, the exchange interaction is used in both quantum gate operation and the measurement of the state of the qubit. The exchange can be controlled electronically by applying gate voltage pulses. We…
Mechanical oscillators have been demonstrated with very high quality factors over a wide range of frequencies. These also couple to a wide variety of fields and forces, making them ideal as sensors. The realization of a mechanically-based…
We demonstrate the transmission of single electron wavepackets from a clock-controlled source through an empty high-energy edge channel. The quantum dot source is loaded with single electrons which are then emitted with high kinetic energy…
Electronic transport through a two-path triple-quantum-dot system with two source leads and one drain is studied. By separating the conductance of the two double dot paths, we are able to observe double dot and triple dot physics in…
We propose and demonstrate experimentally a novel design of single-electron quantum dots. The structure consists of a narrow band gap quantum well that can undergo a transition from the hole accumulation regime to the electron inversion…
We present a simple technique which uses a self-aligned oxide etch to suspend individual single-wall carbon nanotubes between metallic electrodes. This enables one to compare the properties of a particular nanotube before and after…