Related papers: Artificial molecular quantum rings: Spin density f…

Quantum dots are small conductive regions in a semiconductor, containing a variable number of electrons (N=1 to 1000) that occupy well defined discrete quantum states. They are often referred to as artificial atoms with the unique property…

The quantum tunneling effects between two metallic plates are studied using the time dependent density functional theory. Results show that the tunneling is mainly dependent on the separation and the initial local field of the interstice…

We define two laterally gated small quantum dots (~ 15 electrons) in an Aharonov-Bohm geometry in which the coupling between the two dots can be broadly changed. For weakly coupled quantum dots we find Aharonov-Bohm oscillations. In an…

We show that a large number of ions stored in a Penning trap, and forming a 2D Coulomb crystal, provides an almost ideal system for scalable quantum computation and quantum simulation. In particular, the coupling of the internal states to…

In this theoretical work, we study a double quantum dot interacting strongly with a microcavity, while undergoing resonant tunneling. Effects of interdot tunneling on the light-matter hybridized states are determined, and tunability of…

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…

Using the method of breaking of circular symmetry and of subsequent symmetry restoration via projection techiques, we present calculations for the ground-state energies and excitation spectra of N-electron parabolic quantum dots in strong…

Recent advancement in fabrication technologies enable the construction of nano-objects with rather rich internal structures such as double or triple quantum dots, which can then be regarded as artificial molecules. The main new ingredient…

Single electron tunneling is studied in a many electron quantum dot in high magnetic fields. For such a system multiple transitions of the spin configuration are theoretically predicted. With a combination of spin blockade and Kondo effect…

A new family of supramolecular, antiferromagnetically exchange-coupled dimers of single-molecule magnets (SMMs) has recently been reported [W. Wernsdorfer, N. Aliaga-Alcalde, D.N. Hendrickson, and G. Christou, Nature 416, 406 (2002)]. Each…

Hyperfine interaction of electron spins with nuclear spins, in coupled double quantum dots is studied. Results of successive electron spin measurements exhibit bunching due to correlations induced via the nuclear spins. Further nuclear…

We have investigated numerically the electron addition spectra in quantum dots containing a small number (N < 11) of interacting electrons, in presence of strong disorder. For a short-range Coulomb repulsion, we find regimes in which two…

Some of the most intriguing problems in solid state physics arise when the motion of one electron dramatically affects the motion of surrounding electrons. Traditionally, such highly-correlated electron systems have been studied mainly in…

We suggest a simple approach to calculate the local density of states that effectively applies to any structure created by an axially symmetric potential on a continuous graphene sheet such as circular graphene quantum dots or rings.…

It is experimentally demonstrated that an arbitrary quantum state of a single spin 1/2: a|u> + b|d> can be converted into a superposition of the two ferromagnetic states of a spin cluster: a|uu...uu> + b|dd...dd>. The physical system is a…

When a cerocene molecule is chemisorbed on metallic substrate, or when an asymmetric double dot is hybridized with itinerant electrons, its singlet ground state crosses its lowly excited triplet state, leading to a competition between the…

A new quantum approach is presented that can account for the description of small ferromagnetic particles magnetization tunneling. An estimate of the saturation value of an external applied magnetic field along the easy axis is obtained. An…

We introduce a complex-extended continuum level density and apply it to one-dimensional scattering problems involving tunneling through finite-range potentials. We show that the real part of the density is proportional to a real "time…

We consider the full driven quantum dynamics of a qubit realized as spin of electron in a one-dimensional double quantum dot with spin-orbit coupling. The driving perturbation is taken in the form of a single half-period pulse of electric…

Molecular spin clusters are mesoscopic systems whose structural and physical features can be tailored at the synthetic level. Besides, their quantum behavior is directly accessible in laboratory and their magnetic properties can be…