Related papers: Quantum pumping with adiabatically modulated barri…
We present a theoretical study of quantum charge pumping with a single ac gate applied to graphene nanoribbons and carbon nanotubes operating with low resistance contacts. By combining Floquet theory with Green's function formalism, we show…
We theoretically study a current switch that exploits the phase acquired by a charge carrier as it tunnels through a potential barrier in graphene. The system acts as an interferometer based on an armchair graphene quantum ring, where the…
We present results for non-adiabatic single-parameter pumping in a ballistic graphene field-effect transistor. We investigate how scattering from an ac-driven top gate results in dc charge current from source to drain in an asymmetric setup…
The adiabatic motion of a charged, spinning, quantum particle in a two - dimensional magnetic field is studied. A suitable set of operators generalizing the cinematical momenta and the guiding center operators of a particle moving in a…
We investigate pure spin pumping in graphene by imposing a ferromagnet (F) with rotating magnetization on top of it. Using the generalized scattering approach for adiabatic spin pumping, we obtain the spin current pumped through magnetic…
We study directed transport in periodically forced scattering systems in the regime of fast and strong driving where the dynamics is mixed to chaotic and adiabatic approximations do not apply. The model employed is a square potential well…
We consider a classical overdamped Brownian particle moving in a symmetric periodic potential. We show that a net particle flow can be produced by adiabatically changing two external periodic potentials with a spatial and a temporal phase…
We introduce a mathematical setup for charge transport in quantum pump connected to a number of external leads. It is proved that under rather general assumption on the Hamiltonian describing the system, in the adiabatic limit, the current…
The spin orbit effect in graphene is too muted to have any observable significance with respect to its application in spintronics. However, graphene technology is too valuable to be rendered impotent to spin transport. In this communication…
We clarify the role of non-adiabatic effects in a quantum pumping for a spin-boson system. When we sinusoidally control the temperatures of two reservoirs with \pi/2 phase difference, we find that the pumping current strongly depends on the…
Massless Dirac particles cannot be confined by an electrostatic potential. This is a problem for making graphene quantum dots but confinement can be achieved with a magnetic field and here, general conditions for confined and deconfined…
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 have investigated the transport characteristics of an electron pump consisting of an asymmetric double quantum dot at zero bias voltage which is subject to electromagnetic radiation. Depending on the energies of the intermediate states…
We propose schemes for generating spin currents into a semiconductor by adiabatic or non-adiabatic pumping of electrons through interacting quantum dots. The appeal of such schemes lies in the possibility to tune the pumping characteristics…
We investigate charge and spin transport through an adiabatically driven, strongly interacting quantum dot weakly coupled to two metallic contacts with finite bias voltage. Within a kinetic equation approach, we identify coefficients of…
Nanoscopic rings pierced by external magnetic fields and asymmetrically connected to wires behave in sharp contrast with classical expectations. By studying the real-time evolution of tight-binding models in different geometries, we show…
We introduce a model for a flux-assisted Cooper-pair pump, the sluice, which is used to study geometric charge transport. Our model allows for a nonvanishing loop inductance going beyond the usual treatment with an exact phase bias. We…
We show that the feature of Klein tunneling makes graphene a unique interface for implementing low control quantum gates between static and mobile qubits. A ballistic electron spin is considered as the mobile qubit, while the static qubit…
We study the quantum spin pumping of an antiferromagnetic spin-1/2 chain with competing exchange interactions. We show that spatially periodic potential modulated in space and time acts as a quantum spin pump. In our model system, an…
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…