Related papers: Non-adiabatic quantized charge pumping with tunabl…
In adiabatic Cooper pair pumps, operated by means of gate voltage modulation only, the quantization of the pumped charge during a cycle is limited due to the quantum coherence of the macroscopic superconducting wave function. In this work…
We investigate nonequilibrium transport in a triple-quantum-dot (TQD) system, where the central dot acts as a discrete tunnel barrier, subject to continuous monitoring by a quantum point contact (QPC) that is capacitively coupled to all…
The generation of ac modulated quantized current waveforms using a semiconductor non-adiabatic single electron pump is demonstrated. In standard operation the single electron pump generates a quantized output current of I = ef where e is…
We investigate the influence of the Coulomb interaction on the adiabatic pumping current through quantum dots. Using nonequilibrium Green's functions techniques, we derive a general expression for the current based on the instantaneous…
We propose a random matrix theory to describe the influence of a time-dependent external field on electron transport through open quantum dots. We describe the generation of the current by an oscillating field for the dot, connected to two…
We propose a mechanism by which an open quantum dot driven by two ac (radio frequency) gate voltages in the presence of a moderate in-plane magnetic field generates a spin polarized, phase coherent dc current. The idea combines adiabatic,…
In quantum metrology, semiconductor single-electron pumps are used to generate accurate electric currents with the ultimate goal of implementing the emerging quantum standard of the ampere. Pumps based on electrostatically defined tunable…
We derived a general and exact expression of current for quantum parametric charge pumps in the non-adiabatic regime at finite pumping frequency and finite driving amplitude. The non-perturbative theory predicts a remarkable plateau…
We consider adiabatic pumping of electrons through a quantum dot. There are two ways to operate the pump: to create a dc current ${\bar I}$ or to create a dc voltage ${\bar V}$. We demonstrate that, for very slow pumping, ${\bar I}$ and…
We describe a novel mechanism for charge pumping through tunnel-coupled quantum dots in the regime of strong Coulomb blockade. The quantum state of an additional electron within the structure is steered by changing the tunneling couplings…
We provide provide a detailed study of biasless coherent transport of singlet electron pairs in one-dimensional (1D) channels induced by electron-electron interactions that are time-varying in certain spatially localized regions of the…
A quantum pumping mechanism which produces dc current or voltage in response to a cyclic deformation of the confining potential in an open quantum dot is reported. The voltage produced at zero current bias is sinusoidal in the phase…
We study adiabatic pumping through a two-level quantum dot with spin-orbit coupling. Using a diagrammatic real-time approach, we calculate both the pumped charge and spin for a periodic variation of the dot's energy levels in the limit of…
When parameters are varied periodically, charge can be pumped through a mesoscopic conductor without applied bias. Here, we consider the inverse effect in which a transport current drives a periodic variation of an adiabatic degree of…
We present a theoretical proposal of a tunable charge qubit, hosted in triple quantum dots. The manipulation is solely performed by changing the heights of the two potential barriers between the three dots, while the energy of all three…
We investigate the pumped charge and spin at zero-bias by adiabatic modulation of two control parameters using the full counting statistics with quantum master equation approach. First we study higher order effects of the pumping frequency…
We present a theoretical study of the electronic transport through a many-level quantum dot driven by time-dependent signals applied at the contacts to the leads. If the barriers oscillate out of phase the system operates like a turnstile…
We analyze the coupling of qubits mediated by a tunable and fast element beyond the adiabatic approximation. The nonadiabatic corrections are important and even dominant in parts of the relevant parameter range. As an example, we consider…
Quantum pumping through mesoscopic quantum dots is known to be enhanced by resonant transmission. The pumped charge is close to an integer number of electrons when the pumping contour surrounds a resonance, but the transmission remains…
Recent demonstrations using electron spins stored in quantum dots array as qubits are promising for developing a scalable quantum computing platform. An ongoing effort is therefore aiming at the precise control of the quantum dots…