Strongly correlated systems

Anisimov V I, Aryasetiawan F and Liechtenstein A I 1997 First-principles calculations of the electronic structure and spectra of strongly correlated systems The LDA+U method J. Phys. Condens Matters 767... 

M. Nakata, M. Ehara, and H. Nakatsuji, Density matrix variational theory apphcation to the potential energy surfaces and strongly correlated systems. J. Chem. Phys. 116, 5432 (2002). 

A. O. Gogolin, A. A. Nersesyan, A. M. Tsvelik, Bosonization and Strongly Correlated Systems (Cambridge University Press, Cambridge, 1998)... 

Competing ground states and quantum criticality present a special interest of modem physics of strongly correlated systems and most of emergent materials [1, 2], The lightly doped Cu xMxGeO has demonstrated a competition of a dimerized spin-Peierls (SP) phase and a 3D AFM phase, which replace each other under temperature decrease [3-5], The microscopic mechanism of this replacement and phase coexistence (phase separation) could be a subject of magnetic resonance spectroscopy. 

The HF method treats electron-electron interactions at a mean field level, with the Hartree and exchange interactions exactly written. The method can be implemented either in its spin restricted form (RHF), for closed shell systems, or in the unrestricted form (UHF) for open-shell or strongly correlated systems. In the first case, the one-electron orbitals are identical for electrons of both spin directions, while UHF can account for a non-uniform spin density. The one electron orbitals, which are determined in the course of the self-consistent resolution of the HF equations, are expanded on an over-complete basis set of optimized variational functions. 

G. Coslovich, C. Gianneti, et al. Lectures on the physics of strongly correlated systems XIII, edited by A. Avella and F. Mancini. (2009)... 

J. Miranda, V. Kabanov, J. Supercond. Nov. Magn. 22, 287 (2009) and references therein. Also in charge inhomogeneities in strongly correlated systems by A. Castro and C. Morals in the book Strong interaction in low dimensions systems , edit. Springer (2004)... 

F. Alet, P. Dayal, A. Grzesik, A. Honecker, M. Korner, A. Lauchli, S. Man-mana, I. McCulloch, F. Michel, R. Noack, G. Schmid, U. Schollwock, F. Stockli, S. Todo, S. Trebst, M. Troyer, P. Werner, and S. Wessel (2005) The ALPS project open source software for strongly correlated systems. J. Phys. Soc. Jpn. Suppl. 74, p. 30... 

Josephson plasmons are less noisy and more entangled for strongly correlated system. 

The validity of Janak s theorem in OFT opens up the prospect of incorporating ab initio methods into Landau theory for applications to strongly correlated systems, especially when combined with the procedure of integrating over fractional occupation numbers to obtain physical energy differences. 

The energy gap obtained in such band-structure calculations is the one called HOMO-LUMO gap in molecular calculations, i.e., the difference between the energies of the highest occupied and the lowest unoccupied singleparticle states. Neglect of the derivative discontinuity A, defined in Eq. (65), by standard local and semilocal xc functionals leads to an underestimate of the gap (the so-called band-gap problem ), which is most severe in transition-metal oxides and other strongly correlated systems. Self-interaction corrections provide a partial remedy for this problem [71, 72, 73, 74],... 

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