Related papers: Gate-controllable spin-battery
We consider low temperature transport through a lateral quantum dot asymmetrically coupled to two conducting leads, and tuned to the mixed-valence region separating two adjacent Coulomb blockade valleys with spin S=1/2 and S=1 on the dot.…
We propose a spin cell based on photon-assisted tunneling through a conventional semiconductor barrier. The Dresselhaus spin-orbit interaction is included to break the spin rotation symmetry. Due to the in-plane electric field induced…
We investigate a heat- to charge-current converter consisting of a single-level quantum dot coupled to two ferromagnetic metals and one ferromagnetic insulator held at different temperatures. We demonstrate that this nano engine can act as…
A solar cell illuminated by circularly-polarized light generates charge and spin currents. We show that the spin polarization of the current significantly exceeds the spin polarization of the carrier density for the majority carriers. Based…
Pure spin currents are shown to be generated by an electrically controlled quantum pump applied at the edges of a topological insulator. The electric rather than the more conventional magnetic control offers several advantages and avoids,…
Based on electron spins in semiconductor quantum dots as qubits, a new quantum controlled-NOT(CNOT) gate is constructed in solid nanostructure without resorting to spin-spin interactions. Single electron tunneling technology and coherent…
We demonstrate a spin pump to generate pure spin current of tunable intensity and polarization in the absence of charge current. The pumping functionality is achieved by means of an ac gate voltage that modulates the Rashba constant…
Controlling magnetism through non-magnetic means is highly desirable for future electronic devices, as such means typically have ultra-low power requirements and can provide coherent control. In recent years, great experimental progress has…
We demonstrate that spin current can be generated by an ac voltage in a one-channel quantum wire with strong repulsive electron interactions in the presence of a non-magnetic impurity and uniform static magnetic field. In a certain range of…
Photovoltaic effect, e.g., solar cells, converts light into DC electric current. This phenomenon takes place in various setups such as in noncentrosymmetric crystals and semiconductor pn junctions. Recently, we proposed a theory for…
We predict that in a narrow gap III-V semiconductor quantum well or a wire an observable spin current can be generated with a time dependent gate to modify the Rashba spin-orbit coupling constant. Methods to rectify the so generated AC…
We investigate persistent charge and spin currents in a magnetic quantum ring threaded by an Aharonov-Bohm flux, in the presence of a side-coupled one-dimensional non-magnetic chain. The neighboring magnetic moments in the ring are arranged…
We describe an opto-electronic structure in which charge and spin degrees of freedom in electrical gate-defined quantum dots can be coherently coupled to light. This is achieved via electron-electron interaction or via electron tunneling…
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…
We propose a novel scheme to efficiently polarize and manipulate the electron spin in a quantum dot. This scheme is based on the spin-orbit interaction and it possesses following advantages: (1) The direction and the strength of the spin…
We investigate parametric pumping of a spin-polarized current through a nearly-closed quantum dot in a perpendicular magnetic field. Pumping is achieved by tuning the tunnel couplings to the left and right lead - thereby operating the…
Quantum spin Hall insulators, recently realized in HgTe/(Hg,Cd)Te quantum wells, support topologically protected, linearly dispersing edge states with spin-momentum locking. A local magnetic exchange field can open a gap for the edge…
We study heat transport in quantum spin systems analytically and numerically. First, we demonstrate that heat current through a two-level quantum spin system can be modulated from zero to a finite value by tuning a magnetic field. Second,…
We report coherent operation of a singlet-triplet qubit controlled by the arrangement of two electrons in an adjacent double quantum dot. The system we investigate consists of two pairs of capacitively coupled double quantum dots fabricated…
We show that the injection of a pure spin current (not accompanied by charge current) into a ring can induce a circulating charge current in the ring, provided that transport coefficients of the ring are spin-dependent and inhomogeneous. As…