Related papers: Quasiparticle evolution and pseudogap formation in…
We review the contribution of infrared spectroscopy to the study of the pseudogap in high temperature superconductors. The pseudogap appears as a depression of the frequency dependent conductivity in the c-axis direction and seems to be…
The presence of nonmagnetic impurities in a 2D ``bad metal'' depresses the superconducting Berezinskii-Kosterlitz-Thouless transition temperature, while leaving the pairing energy scale unchanged. Thus the region of the pseudogap…
The in-plane optical conductivity of UPd_2Al_3 was measured at temperatures $2 {\rm K}<T<300$ K in the spectral range from 1 cm^{-1} to 40 cm^{-1} (0.14 meV to 5 meV). As the temperature decreases below 25 K a well pronounced pseudogap of…
We perform time resolved photoelectron spectroscopy measurements of optimally doped $\tn{Bi}_2\tn{Sr}_2\tn{CaCu}_2\tn{O}_{8+\delta}$ (Bi-2212) and $\tn{Bi}_2\tn{Sr}_{2-x}\tn{La}_{x}\tn{Cu}\tn{O}_{6+\delta}$ (Bi-2201). The electrons dynamics…
A model incorporating simultaneous superconducting and lattice instabilities has been studied in detail to estimate the nature of coupling and inter-play between them. The phase diagram is obtained in the temperature-filling plane at…
High-temperature superconductivity emerges in the CuO$_2$ plane upon doping a Mott insulator. To ascertain the influence of Mott physics plus short-range correlations, we solve a three-band copper-oxide model in the charge-transfer regime…
The optical conductivity of the heavy fermions UPd2Al3 and UPt3 has been measured in the frequency range from 10 GHz to 1.2 THz (0.04 meV to 5 meV) at temperatures 1 K < T < 300 K. In both compounds a well pronounced pseudogap of less than…
Unpolarized inelastic neutron scattering is used to study the temperature and wave vector dependence of the dynamical magnetic susceptibility, $\chi''(q,\omega)$, of a well characterized single crystal $YBa_2Cu_3O_{6.6}$ ($T_c=62.7$ K). We…
The nature of the pseudogap phase of cuprate high-temperature superconductors is a major unsolved problem in condensed matter physics. We studied the commencement of the pseudogap state at temperature T* using three different techniques…
In-plane Nernst signal and resistivity have been measured for three $La_{2-x}Sr_xCuO_4$ single crystals (x=0.09, 0.11 and 0.145) with the magnetic field parallel to c-axis. A quadratic temperature dependence of resistivity, i.e.,…
Heat transport in the cuprate superconductors YBa$_2$Cu$_3$O$_{y}$ and La$_{2-x}$Sr$_x$CuO$_4$ was measured at low temperatures as a function of doping. A residual linear term kappa_{0}/T is observed throughout the superconducting region…
The pseudogap refers to an enigmatic state of matter with unusual physical properties found below a characteristic temperature $T^*$ in hole-doped high-temperature superconductors. Determining $T^*$ is critical for understanding this state.…
We present a theory for the pseudo-gap state recently observed at the LaAlO3/SrTiO3 interface, based on superconducting islands embedded in a metallic background. Superconductivity within each island is BCS-like, and the local critical…
Many complex electronic systems exhibit so-called pseudogaps, which are poorly-understood suppression of low-energy spectral intensity in the absence of an obvious gap-inducing symmetry. Here we investigate the superconductor…
The nature of the pseudogap in high transition temperature (high-Tc) superconducting cuprates has been a major issue in condensed matter physics. It is still unclear whether the high-Tc superconductivity can be universally associated with…
The in-plane and out-of-plane surface impedance and microwave conductivity components of one and the same YBa_2Cu_3O_{7-x} (0.07\le x\le 0.47) single crystal are determined in the wide ranges of temperature T and carrier concentration p in…
Pseudogap (PG), a phenomenon of opening of gap like features above superconducting (SC) transition temperature (Tc), has been universally observed in the high-Tc cuprates (HTC) (1,2), some heavy fermion superconductors (3), and iron…
We have performed an ultrahigh-resolution angle-resolved photoemission spectroscopy study of slightly-overdoped (Bi,Pb)2Sr2CuO6 to elucidate the origin of pseudogap. By using a newly developed xenon-plasma light source, we determined the…
The nature of the pseudogap phase is a central problem in the quest to understand high-Tc cuprate superconductors. A fundamental question is what symmetries are broken when that phase sets in below a temperature T*. There is evidence from…
The first indication of a pseudogap in cuprates came from a sudden decrease of NMR Knight shift at a doping-dependent temperature $T^*(\delta)$. Since then, experiments have found phase transitions at a lower $T^*_\text{phase}(\delta)$.…