Related papers: Mono-parametric quantum charge pumping: interplay …
We analyze the possible quantum correlations between two coupled dimer systems in the presence of independent losses and driven by a fluctuating field. For the case of the interaction being of a Heisenberg exchange type, we first…
We propose to pump semiconductor quantum dots with surface acoustic waves which deliver an alternating periodic sequence of electrons and holes. In combination with a good optical cavity such regular pumping could entail anti-bunching and…
Quantum rings connected to ballistic circuits couple strongly to external magnetic fields if the connection is not symmetric. By analytical theory and computer simulation I show that properly connected rings can be used to pump currents in…
We consider the phenomenon of quantum charge pumping of electrons across a superconducting double barrier structure in graphene in the adiabatic limit. In this geometry, quantum charge pumping can be achieved by modulating the amplitudes…
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…
The most typical ingredient of topologically protected quantum states are magnetic fluxes. In a system of spins, complex-valued interaction parameters give rise to a flux, if their phases do not add up to zero along a closed loop. Here we…
We derive a Floquet-like formalism to calculate the stationary average current through an AC driven double quantum dot in presence of dissipation. The method allows us to take into account arbitrary coupling strengths both of a…
We study electron pumps in the absence of interference effects paying attention to the spin degree of freedom. Electron-electron exchange interactions combined with a variation of external parameters, such as magnetic field and gate…
We optically probe and electrically control a single artificial molecule containing a well defined number of electrons. Charge and spin dependent inter-dot quantum couplings are probed optically by adding a single electron-hole pair and…
A theory of entangled photons emission from quantum dot in microcavity under continuous and pulsed incoherent pumping is presented. It is shown that the time-resolved two-photon correlations drastically depend on the pumping mechanism: the…
We calculate the charge current in a metallic ferromagnet to first order in the time derivative of the magnetization direction. Irrespective of the microscopic details, the result can be expressed in terms of the conductivities of the…
We consider two one-dimensional quantum $XX$ magnets linked by a periodically driven quantum point contact (QPC). If magnets are initially polarized in opposite directions, one expects that a spin current through the QPC will establish. It…
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…
We develop a time-dependent nonequilibrium Green function (NEGF) approach to the problem of spin pumping by precessing magnetization in one of the ferromagnetic layers within F/I/F magnetic tunnel junctions (MTJs) or F/I/N semi-MTJs in the…
We analyze inelastic cotunneling through an interacting quantum dot subject to an ambient magnetic field in the weak tunneling regime under a non-adiabatic time-dependent bias-voltage. Our results clearly exhibit photon-assisted satellites…
We study synchronized quantized charge pumping through several dynamical quantum dots (QDs) driven by a single time modulated gate signal. We show that the main obstacle for synchronization being the lack of uniformity can be overcome by…
Pumping of electrons through nano-scale devices is one of the fascinating achievements in the field of nano-science with a wide range of applications. To optimize the performance of pumps, operating them at high frequencies is mandatory. We…
We study the appearance of directed current in tunnel junctions, quantum ratchet effect, in the presence of an external ac field f(t). The current is established in a one-dimensional discrete inhomogeneous "tight-binding model". By making…
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…
Recent theoretical calculations, demonstrating that quantized charge transfer due to adiabatically modulated potentials in mesoscopic devices can result purely from the interference of the electron wave functions (without invoking…