Related papers: Resonant tunneling-based spin ratchets
We introduce a solvable model of a nonlinear double-barrier structure, described by a generalized effective-mass equation with a nonlinear coupling term. This model is interesting in its own right for possible new applications, as well as…
We consider spin-polarized transport in a quantum spin Hall antidot system coupled to normal leads. Due to the helical nature of the conducting edge states, the screening potential at the dot region becomes spin dependent without external…
A scheme for a spin polarization direction switch is investigated by studying the spin-dependent electron transport of an asymmetrical quantum wire (QW) with Rashba spin-orbit coupling (SOC). It is found that the magnitude of the…
We propose three different mechanisms for pumping spin-polarized currents in a ballistic circuit using a time-dependent magnetic field acting on an asymmetrically connected quantum ring at half filling. The first mechanism works thanks to a…
It is shown that the excitation of charge carriers by ac electric field with zero average driving leads to a direct electric current in quantum well structures. The current emerges for both linear and circular polarization of the ac…
Spin qubits based on interacting spins in double quantum dots have been successfully demonstrated. Readout of the qubit state involves a conversion of spin to charge information, universally achieved by taking advantage of a spin blockade…
We consider the charge shuttle proposed by Gorelik {\em et al.} driven by a time-dependent voltage bias. In the case of asymmetric setup, the system behaves as a rachet. For pure AC drive, the rectified current shows a complex frequency…
We present evidence that tunneling processes in near-integrable systems are enhanced due to the manifestation of nonlinear resonances and their respective island chains in phase space. A semiclassical description of this…
We report a study of spin dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead (NM-QD-FM). We use the master equation approach to calculate the spin-resolved currents in the…
We study a pseudo-spin-1/2 quantum dot in the cotunneling regime close to the particle-hole symmetric point. For a generic tunneling matrix we find a generic fixed point with interesting nonequilibrium properties, characterized by effective…
We employ a method involving coherent periodic modulation of Raman laser intensity to induce resonance transitions between energy levels of a spin-orbit coupled atom in a symmetric double-well trap. By integrating photon-assisted tunneling…
Advances in fabrication and control of quantum dots allow the realization of metastructures that may exhibit novel electrical transport phenomena. Here, we investigate the electrical current passing through one such metastructure, a system…
We consider a double quantum dot coupled to two normal leads and one superconducting lead, modeling the Cooper pair beam splitter studied in two recent experiments. Starting from a microscopic Hamiltonian we derive a general expression for…
A quantum dot with spin-orbit interaction can work as an efficient spin filter if it is connected to N (> 2) external leads via tunnel barriers. When an unpolarized current is injected to a quantum dot from a lead, polarized currents are…
We study the tunneling of conduction electrons through a (110)-oriented single-barrier heterostructure grown from III-V semiconductor compounds. It is shown that, due to low spatial symmetry of such a barrier, the tunneling current through…
We propose a lateral spin-blockade device that uses an InGaAs/InAlAs double quantum well (DQW), where the values of the Rashba spin-orbit parameter $\alpha_{\rm R}$ are opposite in sign but equal in magnitude between the constituent quantum…
We consider electrical transport through molecules with Heisenberg-coupled spins arranged in a ring structure in the presence of an easy-axis anisotropy. The molecules are coupled to two metallic leads and a gate. In the charged state of…
We present a theoretical analysis of the nonlinear bias and temperature dependence of current-voltage characteristics of a spin-valve device which is formed by connecting a quantum dot to two ferromagnetic electrodes whose magnetic moments…
We investigate the energy spectrum of the biaxial spin systems with magnetic field along the hard anisotropy axis by using the complex periodic orbit theory. All important features of the system appearing in whole energy range, such as…
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…