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Yuriy Skorenkyy

Publications and source records attributed to Yuriy Skorenkyy.

3 recordsLinked to original sources

Mott-Hubbard localization in model of electronic subsystem of doped fullerides

Microscopical model of a doped fulleride electronic subsystem taking into account the triple orbital degeneracy of energy states is considered within the configurational-operator approach. Using the Green function method the energy spectrum of the model at integer band filling $n=1$ is calculated, which case corresponds to $AC_{60}$ compounds. Possible correlation-driven metal-insulator transition in the model is discussed.

cond-mat.str-el

Phase Diagram of Metal-Insulator Transition in System with Anderson-Hubbard Centers

The model of a strongly correlated system in which periodically spaced Anderson-Hubbard centers are introduced into narrow-band metal is considered. Besides the interactions between localized magnetic moments and strong on-site Coulomb interaction, the model takes into account the hybridization of localized and band states. To study the efect of the lattice deformation on the electrical properties of the system the phonon term and elastic energy have been taken into account. Green functions for band and localized electrons have been found. On this base, the energy spectrum has been investigated as function of model parameters, temperature and external pressure. The criterion of metal-insulator transition for integer value of electron concentration has been derived and the phase diagram of the metal-insulator transition has been built.

cond-mat.str-el

Electron Correlations in Narrow Energy Bands: Ground State Energy and Metal-Insulator Transition

The electron correlations in narrow energy bands are examined in framework of the Hubbard model. The single-particle Green function and energy spectrum are obtained in paramagnetic state at half-filling by means of new two-pole approximation. In the ground state analitical expressions for the energy gap, polar states concentration and energy of the system are found. Metal-insulator transitions in the model at change of bandwidth or temperature are investigated. The obtained results are used for interpretation of some experimental data in narrow-band materials.

cond-mat.str-el