Polaron coherence as origin of the pseudogap phase in high temperature superconducting cuprates
نویسندگان
چکیده
Within a two-component approach to high T c copper oxides including polaronic couplings, we identify the pseudogap phase as the onset of polaron ordering. This ordering persists in the superconducting phase. A huge isotope effect on the pseudogap onset temperature T * is predicted and in agreement with experimental data. The anomalous temperature dependence of the mean square copper-oxygen ion displacement observed above, at and below T c , stems from an s-wave superconducting component of the order parameter, whereas a pure d-wave order parameter alone can be excluded.
منابع مشابه
Superconductivity in Fe and As based compounds: A bridge between MgB2 and cuprates
By interpreting various experimental data for the new high temperature FeAs type superconductors in terms of lattice mediated multigap superconductivity, it is shown that these systems strongly resemble MgB2, however, with the distinction that local polaronic lattice effects exist. This fact establishes a connection to cuprate high temperature superconductors where polaron formation is essentia...
متن کاملStripe-like Inhomogeneities, Coherence, and the Physics of the High Tc Cuprates
The carriers in the high-Tc cuprates are found to be polaron-like “stripons” carrying charge and located in stripe-like inhomogeneities, “quasi-electrons” carrying charge and spin, and “svivons” carrying spin and some lattice distortion. The anomalous spectroscopic and transport properties of the cuprates are understood. The stripe-like inhomogeneities result from the Bose condensation of the s...
متن کاملThermodynamics and phase diagram of high temperature superconductors.
Thermodynamic quantities are derived for superconducting and pseudogap regimes by taking into account both amplitude and phase fluctuations of the pairing field. In the normal (pseudogap) state of the underdoped cuprates, two domains have to be distinguished: near the superconducting region, phase correlations are important up to temperature T(phi). Above T(phi), the pseudogap region is determi...
متن کامل1 3 M ar 2 00 2 Fröhlich - Coulomb model of high - temperature superconductivity and charge segregation in the cuprates
Fröhlich-Coulomb model of high-temperature superconductivity and charge segregation in the cuprates. Abstract. We introduce a generic Fröhlich-Coulomb model of the oxides, which also includes infinite on-site (Hubbard) repulsion, and describe a simple analytical method of solving the multi-polaron problem in complex lattice structures. Two particular lattices, a zigzag ladder and a perovskite l...
متن کاملOn the nature of the superconducting gap in the cuprates
Recent experiments indicate that the excitation spectrum of the cuprates is characterised, in the superconducting state, by two energy scales: the “coherence energy” ∆c and the “pseudogap” ∆p. Here we consider a simple generalisation of the BCS model that yields exotic pairing and can describe, phenomenologically, the generic trends in the critical temperature Tc of cuprate superconductors. We ...
متن کامل