相关论文: Quantum rings as electron spin beam splitters

Entangling gates for electron spins in semiconductor quantum dots are generally based on exchange, a short-ranged interaction that requires wavefunction overlap. Coherent spin-photon coupling raises the prospect of using photons as…

We use the spin-polarized excitons in a single quantum dot to design optical controls for basic operations in quantum computing. We examine the ultrafast nonlinear optical processes required and use the coherent nonlinear optical responses…

Coherent control of quantum states is at the heart of implementing solid-state quantum processors and testing quantum mechanics at the macroscopic level. Despite significant progress made in recent years in controlling single- and…

In mesoscopic systems with spin-orbit coupling, spin-injection into quantum dots at zero magnetic field is expected under a wide range of conditions. However, up to now, a viable approach for experimentally identifying such injection has…

Optomechanical systems typically use light to control the quantum state of a mechanical resonator. In this paper, we propose a scheme for controlling the quantum state of light using the mechanical degree of freedom as a controlled beam…

Half-quantum vortices -- topological excitations carrying half the superconducting flux quantum -- are predicted to emerge in spin-triplet superconductors, where the spin component of order parameter enables fractional flux quantization. We…

Electron spin qubits in semiconductors are attractive from the viewpoint of long coherence times. However, single spin measurement is challenging. Several promising schemes incorporate ancillary tunnel couplings that may provide unwanted…

Injecting spin-polarized carriers into semiconductor lasers provides important opportunities to extend what is known about spintronic devices, as well as to overcome many limitations of conventional (spin-unpolarized) lasers. By developing…

We theoretically investigate quantum interference of two single photons at a lossy asymmetric beam splitter, the most general passive 2$\times$2 optical circuit. The losses in the circuit result in a non-unitary scattering matrix with a…

The states of two electrons in tunnel-coupled semiconductor quantum dots can be effectively described in terms of a two-spin Hamiltonian with an isotropic Heisenberg interaction. A similar description needs to be generalized in the case of…

In solid_state hybrid electron_nuclear spin systems quantum entanglement plays vital role in allowing accessible transfer of information between subatomic particles, regardless of the host lattice coordination spatial geometry, revealing…

We propose a spintronic device to generate spin polarization in a mesoscopic region by purely electric means. We show that the spin Hall effect in combination with the stirring effect are sufficient to induce measurable spin polarization in…

Many-particle electron states in semiconductor quantum dots with carrier-mediated ferromagnetism are studied theoretically within the self-consistent Boltzmann equation formalism. Depending on the conditions, a quantum dot may contain there…

The Coulomb interactions between electrons play important roles in coupling multiple qubits in various quantum systems. Here we demonstrate controlled quantum operations of three electron charge qubits based on three capacitively coupled…

We study the motion of a charged quantum particle, constrained on the surface of a cylinder, in the presence of a radial magnetic field. When the spin of the particle is neglected, the system essentially reduces to an infinite family of…

We show theoretically that a strongly spin-polarized current can be generated in semiconductors by taking advantage of the ferromagnetic phase of a quantum dot array (QDA). A Hubbard model with coupling to leads is used to study the…

Device concepts in semiconductor spintronics make long spin lifetimes desirable, and the requirements put on spin control by schemes of quantum information processing are even more demanding. Unfortunately, due to spin-orbit coupling…

The structural inversion asymmetry-induced spin-orbit interaction of conduction band electrons in zinc-blende and wurtzite semiconductor structures is analysed allowing for a three-dimensional (3D) character of the external electric field…

We review spin properties of semiconductor quantum dots and their effect on optical spectra. Photoluminescence and other types of spectroscopy are used to probe neutral and charged excitons in individual quantum dots with high spectral and…

Semiconductor holes with strong spin-orbit coupling allow all-electrical spin control, with broad applications ranging from spintronics to quantum computation. Using a two-dimensional hole system in a GaAs quantum well, we demonstrate a new…