Related papers: Quantum Spin Current Induced Through Optical Field…
We present an introductory overview of the use of spin chains as quantum wires, which has recently developed into a topic of lively interest. The principal motivation is in connecting quantum registers without resorting to optics. A spin…
We present a proposal for a fully electrically controllable quantum dot based spin current injector. The device consists of a quantum dot that is strongly coupled to a ferromagnetic electrode on one side and weakly coupled to a nonmagnetic…
The spin Hall effect (SHE), which converts a charge current into a transverse spin current, has long been believed to be a phenomenon induced by the spin--orbit coupling. Here, we propose an alternative mechanism to realize the intrinsic…
The orbital Hall effect generates a current of orbital angular momentum perpendicular to a charge current. Experiments suggest that this orbital current decays on a long length scale that is of the order of the spin flip diffusion length or…
Here we explore spin dependent quantum transport through a single quantum dot coupled to an optical microcavity. The spin current is generated by electron tunneling between a single doped reservoir and the dot combined with intradot spin…
We describe a mechanism of spin transfer between individual quantum dots that does not require tunneling. Incident circularly-polarized photons create inter-band excitons with non-zero electron spin in the first quantum dot. When the…
We study nonequilibrium generation of spin-dependent transport through a single-level quantum dot embedded in a ring with the Rashba spin-orbit coupling. We consider nonmagnetic systems, involving no magnetic field nor ferromagnetic leads.…
Photons can carry spin angular momentum (SAM) and orbital angular momentum (OAM), which can be used to realize a qubit system and a high-dimension system respectively. This spin-orbital system is very suitable for implementing…
Electron spins in a semiconductor quantum well couple to an electric field {\it via} spin-orbit interaction. We show that the standard spin-orbit coupling mechanisms can provide extraordinary efficient electron spin manipulation by an…
A seminal gedankenexperiment by Laughlin describes the charge transport in quantum Hall systems via the pumping of flux. Here, we propose an optical scheme which probes and manipulates quantum Hall systems in a similar way: When light…
We predict a mechanism to generate a pure spin current in a two-dimensional topological insulator. As the magnetic impurities exist on one of edges of the two-dimensional topological insulator, a gap is opened in the corresponding gapless…
The covariant Dirac equation and its solutions show that rotation and acceleration can be used to generate and control spin currents.
Numerical calculations indicate that by suitably controlling the individual gate voltages of a capacitively coupled parallel double quantum dot, with each quantum dot coupled to one of two independent non-magnetic channels, this system can…
Manipulation of single spins is essential for spin-based quantum information processing. Electrical control instead of magnetic control is particularly appealing for this purpose, since electric fields are easy to generate locally on-chip.…
Semiconductor point contacts can be a useful tool for producing spin-polarized currents in the presence of spin-orbit (SO) interaction. Neither magnetic fields nor magnetic materials are required. By numerical studies, we show that (i) the…
A longstanding theoretical prediction is the orientation of spins by an electrical current flowing through low-dimensional carrier systems of sufficiently low crystallographic symmetry. Here we show by means of terahertz transmission…
We describe how the three-dimensional quantum spin Hall phase arises from the insulator phase by changing an external parameter. In 3D systems without inversion symmetry, a gapless phase should appear between the two phases with a bulk gap.…
We suggest a new practical scheme for the direct detection of pure spin current by using the two-color Faraday rotation of optical quantum interference process (QUIP) in a semiconductor system. We demonstrate theoretically that the Faraday…
We propose a mechanism for spin polarized photocurrent generation in quantum wires. The effect is due to the combined effect of Rashba spin-orbit interaction, external magnetic field and microwave radiation. The time-independent…
We demonstrate coherent optical control of a single hole spin confined to an InAs/GaAs quantum dot. A superposition of hole spin states is created by fast (10-100 ps) dissociation of a spin-polarized electron-hole pair. Full control of the…