The complexes of Cu2+ hexafluoroacetylacetonate with two pyrazol-substituted nitronyl nitroxides are the choice systems to study the spin dynamics of strongly exchange-coupled spin triads. The large values of exchange coupling (ca. 100 cm-1) and high-resolution electron paramagnetic resonance (EPR) at Q- and W-bands (35 and 94 GHz) allowed us to observe and interpret specific characteristics of...

We have studied the electron exchange-correlation effect on thecharacteristics of the two-component unmagnetized dense quantum plasma withstreaming motion. For this purpose, we have used the quantum hydrodynamic model(including the effects of a quantum statistical Fermi electron temperature) for studyingthe propagation of an electrostatic electron plasma waves in such th...

We use gate voltage control of the exchange interaction to prepare, manipulate, and measure two-electron spin states in a GaAs double quantum dot. By placing two electrons in a single dot at low temperatures we prepare the system in a spin singlet state. The spin singlet is spatially separated by transferring an electron to an adjacent dot. The spatially separated spin singlet state dephases in...

We study the phase diagram of R1−xAxMnO3 (R=La, Pr, Nd, Sm ; A=Ca, Sr, Ba) by taking into account the degeneracy of eg orbitals and the anisotropy of the transfer integral. The electron-electron interaction is treated in the mean field approximation with the optimization of the spin and orbital structures. The global phase diagram is understood in terms of the two interactions, i.e., the super ...

In general, control over the degree of spin orientation of photocreated charge carriers in semiconductor structures is achieved by polarized-light excitation of optical transitions in conformity with the angular momentum selection rules. In semiconductor quantum wells (QWs) the spin dynamics results from the individual dynamics of the electron spin (components 1/2, in units of ~) or heavy hole ...

Nagaoka’s theorem on ferromagnetism in the Hubbard model with one electron fewer than half filling is generalized to the case where all possible nearest-neighbor Coulomb interactions ~the density-density interaction V , bond-charge interaction X , exchange interaction F , and hopping of double occupancies F8) are included. It is shown that for ferromagnetic exchange coupling (F.0) ground states...

One-electron self-interaction and an incorrect asymptotic behavior of the Kohn-Sham exchange-correlation potential are among the most prominent limitations of many present-day density functionals. However, a one-electron self-interaction-free energy does not necessarily lead to the correct long-range potential. This is shown here explicitly for local hybrid functionals. Furthermore, carefully s...