Zobrazeno 1 - 10
of 325
pro vyhledávání: '"Iadonisi G."'
Publikováno v:
Phys. Rev. B 73, 245430 (2006)
A first-principles calculation of the impurity screening in Si and Ge nanocrystals is presented. We show that isocoric screening gives results in agreement with both the linear response and the point-charge approximations. Based on the present ab ini
Externí odkaz:
http://arxiv.org/abs/0801.2312
Publikováno v:
Nanotechnology 19, 025711 (2008)
By combining ab initio all-electron localized orbital and pseudopotential plane-wave approaches we report on calculations of the electron affinity (EA) and the ionization potential (IP) of (5, 5) and (7, 0) single-wall carbon nanotubes. The role play
Externí odkaz:
http://arxiv.org/abs/0801.1961
Publikováno v:
Physical Review B 75, 033312 (2007)
The role of local fields in the optical response of silicon nanocrystals is analyzed using a tight binding approach. Our calculations show that, at variance with bulk silicon, local field effects dramatically modify the silicon nanocrystal optical re
Externí odkaz:
http://arxiv.org/abs/0710.5069
Publikováno v:
Physical Review B 76, 085326 (2007)
We report on a theoretical derivation of the electronic dielectric response of semiconductor nanocrystals using a tight-binding framework. Extending to the nanoscale the Hanke and Sham approach [Phys. Rev. B 12, 4501 (1975)] developed for bulk semico
Externí odkaz:
http://arxiv.org/abs/0705.2163
Publikováno v:
Eur. Phys. J. B 41, 163 (2004)
The formation of spherical polaron clusters is studied within the Fr$\ddot{o}$hlich polaron theory. In a dilute polaron gas, using the non-local statistical approach and the polaron pair interaction obtained within the Pekar strong coupling theory, t
Externí odkaz:
http://arxiv.org/abs/cond-mat/0411653
Autor:
Perroni, C. A., Cataudella, V., De Filippis, G., Iadonisi, G., Marigliano, V., Ventriglia, F.
Publikováno v:
Phys. Rev. B 68, 224424 (2003)
Thickness dependence and strain effects in films of $La_{1-x}A_xMnO_3$ perovskites are analyzed in the colossal magnetoresistance regime. The calculations are based on a generalization of a variational approach previously proposed for the study of ma
Externí odkaz:
http://arxiv.org/abs/cond-mat/0310758
Autor:
Perroni, C. A., Cataudella, V., De Filippis, G., Iadonisi, G., Ramaglia, V. Marigliano, Ventriglia, F.
Publikováno v:
Phys. Rev. B 67, 214301 (2003)
The optical properties of the charge-ordering ($CO$) phase of the one-dimensional (1D) half-filled spinless Holstein model are derived at zero temperature within a well-known variational approach improved including second-order lattice fluctuations.
Externí odkaz:
http://arxiv.org/abs/cond-mat/0302124
Autor:
Perroni, C. A., Cataudella, V., De Filippis, G., Iadonisi, G., Ramaglia, V. Marigliano, Ventriglia, F.
Publikováno v:
Phys. Rev. B 67, 94302 (2003)
The phase diagram of the half-filled spinless Holstein model for electrons interacting with quantum phonons is derived in three dimensions extending at finite temperature $T$ a variational approach introduced for the one-dimensional T=0 case. Employi
Externí odkaz:
http://arxiv.org/abs/cond-mat/0301058
Autor:
Perroni, C. A., Cataudella, V., De Filippis, G., Iadonisi, G., Ramaglia, V. Marigliano, Ventriglia, F.
Employing a variational approach that takes into account electron-phonon and magnetic interactions in $La_{1-x}A_xMnO_3$ perovskites with $0
Externí odkaz:
http://arxiv.org/abs/cond-mat/0203121