Phase separation of electrons strongly coupled with phonons in cuprates and manganites

Details Phase separation of electrons strongly coupled with phonons in cuprates and manganites Phase separation of electrons strongly coupled with phonons in cuprates and manganites

2008-10-23

arxiv.org/abs/0810.4277v1

Journal of Superconductivity and Novel Magnetism, v.22, 95 (2009)

Physics

Condensed Matter

Superconductivity

15 pages, 4 figures, invited paper at the International Workshop "Controlling Phase Separation in Electronic Systems - 2008"(3

Scientific paper

Recent advanced Monte Carlo simulations have not found superconductivity and phase separation in the Hubbard model with on-site repulsive electron-electron correlations. We argue that microscopic phase separations in cuprate superconductors and colossal magnetoresistance (CMR) manganites originate from a strong electron-phonon interaction (EPI) combined with unavoidable disorder. Attractive electron correlations, caused by an almost unretarded EPI, are sufficient to overcome the direct inter-site Coulomb repulsion in these charge-transfer Mott-Hubbard insulators, so that low energy physics is that of small polarons and small bipolarons (real-space electron (hole) pairs dressed by phonons). They form clusters localised by disorder below the mobility edge, but propagate as the Bloch states above the mobility edge. I identify the Froehlich finite-range EPI with optical phonons as the most essential for pairing and phase separation in superconducting layered cuprates. The pairing of oxygen holes into heavy bipolarons in the paramagnetic phase (current-carrier density collapse (CCDC)) explains also CMR of doped manganites due to magnetic break-up of bipolarons in the ferromagnetic phase. Here I briefly present an explanation of high and low-resistance phase coexistence near the ferromagnetic transition as a mixture of polaronic ferromagnetic and bipolaronic paramagnetic domains due to unavoidable disorder in doped manganites.

Affiliated with

Also associated with

No associations

Rating

Phase separation of electrons strongly coupled with phonons in cuprates and manganites does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Phase separation of electrons strongly coupled with phonons in cuprates and manganites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase separation of electrons strongly coupled with phonons in cuprates and manganites will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-680856