相关论文: A coherent double-quantum-dot electron pump
We propose a new mode of operation of an electron pump consisting of two weakly coupled quantum dots connected to reservoirs. An electron can be transferred within the device at zero bias voltage when it is subjected to electromagnetic…
We study the impact of off-resonant tunneling and coherences on the electron pumping through quantum dots. Thereby, we focus on two electron-pump setups where lowest-order tunneling processes are suppressed and the pump is exclusively…
We demonstrate single-electron pumping in a gate-defined carbon nanotube double quantum dot. By periodic modulation of the potentials of the two quantum dots we move the system around charge triple points and transport exactly one electron…
Quasi-static transport measurements are employed on a laterally defined tunnel-coupled double quantum dot. A nearby quantum point contact allows us to track the charge as added to the device. If charged with only up to one electron, the…
We analyze time-dependent transport through a quantum dot with electron-electron interaction that is statically tunable to both repulsive and attractive regimes, or even dynamically driven. Motivated by the recent experimental realization…
We demonstrate theoretically that it is possible to use Rabi oscillations to coherently control the electron tunneling in an asymmetric double quantum dot system, a quantum dot molecule. By applying an optical pump pulse we can excite an…
Time-dependent electron transport through a quantum dot and double quantum dot systems in the presence of polychromatic external periodic quantum dot energy-level modulations is studied within the time evolution operator method for a…
Electron transport experiments on two lateral quantum dots coupled in series are reviewed. An introduction to the charge stability diagram is given in terms of the electrochemical potentials of both dots. Resonant tunneling experiments show…
Adiabatically pumped charge, carried by non-interacting electrons through a quantum dot in a turnstile geometry, is studied as function of the strength of the two modulating potentials (related to the conductances of the two point-contacts…
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 present experimental studies of the current pumped through a dynamic quantum dot over a wide range of magnetic fields. At low fields we observe repeatable structure indicating increased confinement of the electrons in the dynamic dot. At…
We employ ultrafast pump-probe spectroscopy to directly monitor electron tunneling between discrete orbital states in a pair of spatially separated quantum dots. Immediately after excitation, several peaks are observed in the pump-probe…
We study DC charge and spin transport through a weakly coupled quantum dot, driven by a non-adiabatic periodic change of system parameters. We generalize the model of Tien and Gordon to simultaneously oscillating voltages and tunnel…
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…
Semiconductor-based quantum dot single-electron pumps are currently the most promising candidates for the direct realization of the emerging quantum standard of the ampere in the International System of Units. Here, we discuss a silicon…
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 study the coherent dynamics of one- and two-electron transport in a linear array of tunnel-coupled quantum dots. We find that this system exhibits a rich variety of coherent phenomena, ranging from electron wavepacket propagation and…
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…
Non-adiabatic charge pumping through a single-level quantum dot with periodically modulated parameters is studied theoretically. By means of a quantum-master-equation approach the full counting statistics of the system is obtained. We find…
Quantum pumping holds great potential for future applications in micro- and nanotechnology. Its main feature, dissipationless charge transport, is theoretically possible via several different mechanisms. However, since no unambiguous…