Related papers: Spin qubits in double quantum dots - entanglement …
We study two tunnel-coupled quantum dots each with a spin 1/2 and attached to leads in the Coulomb blockade regime. We study the interplay between Kondo correlations and the singlet-triplet exchange splitting $K$ between the two spins. We…
A crucial requirement for quantum information processing is the realization of multiple-qubit quantum gates. Here, we demonstrate an electron spin based all-electrical two-qubit gate consisting of single spin rotations and inter-dot spin…
We study the dynamics of entanglement of two electron spins in two quantum dots, in which each electron is interacting with its nuclear spin environment. Focusing on the case of uncoupled dots, and starting from either Bell or Werner states…
We discuss a new entangled state that has been observed in the conduction across a quantum dot. At Coulomb blockade, electrons from the contacts correlate strongly to those localized in the dot, due to cotunneling processes. Because of the…
We study the decay of entanglement of quantum dot electron-spin qubits under hyperfine interaction mediated decoherence. We show that two qubit entanglement of a single entangled initial state may exhibit decay characteristic of the two…
Time evolution of initially prepared entangled state in the system of coupled quantum dots has been analyzed by means of two different theoretical approaches: equations of motion for the all orders localized electron correlation functions,…
We study spectral and transport properties of interacting quantum dots with spin. Two particular model systems are investigated: Lateral multilevel and two parallel quantum dots. In both cases different paths through the system can give…
Quantum computers have the potential to solve certain interesting problems significantly faster than classical computers. To exploit the power of a quantum computation it is necessary to perform inter-qubit operations and generate entangled…
We review our investigation of the spin dynamics for two electrons confined to a double quantum dot under the influence of the hyperfine interaction between the electron spins and the surrounding nuclei. Further we propose a scheme to…
The spin-orbit coupling influences the total spin of semiconductor quantum dots. We analyze the theoretical prediction for the combined effects of spin-orbit coupling, weak vertical magnetic fields and deformation of the dot. Our results…
The total spin of correlated electrons in a quantum dot changes with magnetic field and this effect is generally linked to the change in the total angular momentum from one magic number to another, which can be understood in terms of an…
Achieving control over the electron spin in quantum dots (artificial atoms) or real atoms promises access to new technologies in conventional and in quantum information processing. Here we review our proposal for quantum computing with…
We study the nonequilibrium spin transport through a quantum dot containing two spin levels coupled to the magnetic electrodes. A formula for the spin-dependent current is obtained and is applied to discuss the linear conductance and…
We study the competition between the Kondo effect and the exchange interaction in the parallel double quantum dot(DQDs) system within an effective action field theory. The strong on-site Coulomb interactions in DQDs are treated by using the…
A weakly bound electron in a semiconductor quantum wire is shown to become entangled with an itinerant electron via the coulomb interaction. The degree of entanglement and its variation with energy of the injected electron, may be tuned by…
We propose to use the spin-orbit interaction as a means to control electron spins in quantum dots, enabling both single qubit and two qubit operations. Very fast single qubit operations may be achieved by temporarily displacing the…
We analyze the entanglement properties of spins (qubits) close to the boundary of spin chains in the vicinity of a quantum critical point and show that the concurrence at the boundary is significantly different from the one of bulk spins.…
We examine several well known quantum spin models and categorize behavior of pairwise entanglement at quantum phase transitions. A unified picture on the connection between the entanglement and quantum phase transition is given.
We study a quantum dot connected to the bulk by single-mode junctions at almost perfect conductance. Although the average charge $e\langle N \rangle$ of the dot is not discrete, its spin remains quantized: $s=1/2$ or $s=0$, depending…
Studying quantum properties in solid-state systems is a significant avenue for research. In this scenario, double quantum dots (DQDs) appear as a versatile platform for technological breakthroughs in quantum computation and nanotechnology.…