Friday, February 3, 2012

1112.3230 (A. S. Alexandrov et al.)

Superlight small bipolarons from realistic long-range Coulomb and
Fröhlich interactions
   [PDF]

A. S. Alexandrov, J. H. Samson, G. Sica
We report analytical and numerical results on the two-particle states of the
polaronic t-Jp model derived recently with realistic Coulomb and
electron-phonon (Frohlich) interactions in doped polar insulators. Eigenstates
and eigenvalues are calculated for two different geometries. Our results show
that the ground state is a bipolaronic singlet, made up of two polarons. The
bipolaron size increases with increasing ratio of the polaron hopping integral
t to the exchange interaction Jp but remains small compared to the system size
in the whole range 0to a superconducting state with a critical temperature well in excess of 100K.
In the range t/Jp<1, there are distinct charge and spin gaps opening in the
density of states, specific heat, and magnetic susceptibility well above Tc.
View original: http://arxiv.org/abs/1112.3230

No comments:

Post a Comment