%0 Book Section %1 statphys23_0168 %A Ciuchi, S. %A Sangiovanni, G. %A Capone, M. %B Abstract Book of the XXIII IUPAP International Conference on Statistical Physics %C Genova, Italy %D 2007 %E Pietronero, Luciano %E Loreto, Vittorio %E Zapperi, Stefano %K dynamical field insulator insulators mean metal mott statphys23 superconductivity theory to topic-8 transitions %T Pairing and polarization in systems with retarded interactions %U http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=168 %X In a system where a boson (e.g, a phonon) of finite frequency $ømega_0$ is coupled to lattice fermions, two phenomena occur as the coupling is increased: local fermion pairing via multiple boson exchanges and polarization of the boson field. Within a path integral formalism and a Dynamical Mean-Field approach, we introduce two distribution functions which allow us to pinpoint the two effects. When $ømega_0$ is smaller than the bandwidth $D$, pairing and polarization occur for fairly similar couplings for all considered temperatures. When $ømega_0 > D$, the two phenomena tend to coincide only for $T ømega_0$, but are no longer tied for low temperatures so that a state of locally paired particles without finite polarization is stabilized. The method used can be extended to determine the metal to Mott-insulator crossover at finite temperature.

@incollection{statphys23_0168, abstract = {In a system where a boson (e.g, a phonon) of finite frequency $\omega_0$ is coupled to lattice fermions, two phenomena occur as the coupling is increased: local fermion pairing via multiple boson exchanges and polarization of the boson field. Within a path integral formalism and a Dynamical Mean-Field approach, we introduce two distribution functions which allow us to pinpoint the two effects. When $\omega_0$ is smaller than the bandwidth $D$, pairing and polarization occur for fairly similar couplings for all considered temperatures. When $\omega_0 > D$, the two phenomena tend to coincide only for $T \gg \omega_0$, but are no longer tied for low temperatures so that a state of locally paired particles without finite polarization is stabilized. The method used can be extended to determine the metal to Mott-insulator crossover at finite temperature.}, added-at = {2007-06-20T10:16:09.000+0200}, address = {Genova, Italy}, author = {Ciuchi, S. and Sangiovanni, G. and Capone, M.}, biburl = {https://www.bibsonomy.org/bibtex/232f5c406645ec471251d74770e13875a/statphys23}, booktitle = {Abstract Book of the XXIII IUPAP International Conference on Statistical Physics}, editor = {Pietronero, Luciano and Loreto, Vittorio and Zapperi, Stefano}, interhash = {edc448c3b84563056e3dc1ad0d2557aa}, intrahash = {32f5c406645ec471251d74770e13875a}, keywords = {dynamical field insulator insulators mean metal mott statphys23 superconductivity theory to topic-8 transitions}, month = {9-13 July}, timestamp = {2007-06-20T10:16:13.000+0200}, title = {Pairing and polarization in systems with retarded interactions}, url = {http://st23.statphys23.org/webservices/abstract/preview_pop.php?ID_PAPER=168}, year = 2007 }