Related papers: Polaron Coherence as Origin of the Pseudogap Phase…
To investigate the relationship between the pseudogap and superconductivity, we measured both the in-plane ($\rho_{ab}$) and out-of-plane ($\rho_c$) resistivity for oxygen-controlled Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ single crystals…
We report transport measurements using pulsed magnetic fields to suppress the superconducting fluctuations (SCF) conductivity in a series of YBa_2Cu_3O_(6+x) samples. These experiments allow us altogether to measure the temperature T'c at…
We analyze the anomalies of superconducting state (s and d-wave pairing) in a simple model of pseudogap state, induced by fluctuations of short - range order (e.g. antiferromagnetic), based on the model Fermi surface with "hot patches". We…
The electronic phase diagrams of many highly correlated systems, and in particular the cuprate high temperature superconductors, are complex, with many different phases appearing with similar-sometimes identical-ordering temperatures even…
The mutual interaction between Cooper pairs is proposed as a mechanism for the superconducting state. Above $T_c$, pre-existing but fluctuating Cooper pairs give rise to the unconventional {\it pseudogap} (PG) state, well-characterized by…
The discovery of superconductivity with a critical temperature exceeding 55 K in the iron-oxypnictides and related compounds has quite suddenly given the community a new set of materials - breaking the tyranny of copper. This new class of…
Cuprate high-temperature superconductors are known to have a normal-state pseudogap but, after many years of intense research, its relation to the superconductivity is still a mystery. Similarly, the in-plane Hall coefficient $R_{\rm H}$…
A superconducting state is characterized by the gap in the electronic density of states which vanishes at the superconducting transition temperature Tc. It was discovered that in high temperature superconductors a noticeable depression in…
In this paper we study the effects of the strong coupling superconductivity on the normal state electronic structure. We point out that the pseudogap phenomena in High-T_c cuprates are naturally explained as a precursor of the strong…
The pseudogap phase of the cuprate superconductors is argued to be characterized by a hidden broken symmetry of d-wave character in the particle-hole channel that leads to staggered orbital magnetism. This proposal has many striking…
We studied the temperature dependences of the optical spectra for optimally and underdoped Bi$_2$Sr$_2$Ca$_2$Cu$_3$O$_{10+z}$ single crystals. Similarly to the other cuprates' cases, a gap-like conductivity suppression was observed with…
A recent polarized x-ray absorption experiment on the high temperature cuprate superconductor Bi2Sr2CaCu2O8 indicates the presence of broken parity symmetry below the temperature, T*, where a pseudogap appears in photoemission. We…
In the quest to understand high-temperature superconductivity in copper oxides, a vigorous debate has been focused on the pseudogap - a partial gap that opens over portions of the Fermi surface in the 'normal' state above the bulk critical…
A phase diagram for a 2D metal with variable carrier density has been studied using the modulus-phase representation for the order parameter in a fully microscopic treatment. This amounts to splitting the degrees of freedom into neutral…
We investigate the behavior of the superconducting transition temperature within a previously developed BCS-Bose Einstein crossover picture. This picture, based on a decoupling scheme of Kadanoff and Martin, further extended by Patton, can…
The experimentally measured phase diagram of cuprate superconductors in the temperature-applied magnetic field plane illuminates key issues in understanding the physics of these materials. At low temperature, the superconducting state gives…
Through an analysis and modeling of data from various experimental techniques, we present clear evidence for the presence of a hidden order pseudogap in \U in the temperature range between 25 K and 17.5 K. Considering fluctuations of the…
The study of interaction between different degrees of freedom in solids is of fundamental importance to understand the functionalities of materials. One striking example of such interaction is the intertwined coupling or competition between…
Based on recent experimental results for electron-doped cuprate oxides and ferromagnetic superconductors, it is shown that antiferromagnetic fluctuations always develop in the superconducting phase of both low- and high-temperature…
The polaron binding energy E_{p} in undoped parent cuprates has been determined to be about 1.0 eV from the unconventional oxygen-isotope effect on the antiferromagnetic ordering temperature. The deduced value of E_{p} is in quantitative…